<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">APM</journal-id><journal-title-group><journal-title>Advances in Pure Mathematics</journal-title></journal-title-group><issn pub-type="epub">2160-0368</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/apm.2015.512067</article-id><article-id pub-id-type="publisher-id">APM-60383</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Physics&amp;Mathematics</subject></subj-group></article-categories><title-group><article-title>
 
 
  Farey Triangle Graphs and Farey Triangle Matrices
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>.</surname><given-names>Gnanam</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>C.</surname><given-names>Dinesh</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib></contrib-group><aff id="aff1"><addr-line>Department of Mathematics, Government Arts College, Trichy, India</addr-line></aff><author-notes><corresp id="cor1">* E-mail:<email>gnaanam@yahoo.com(.G)</email>;<email>dinesh.c916@gmail.com(CD)</email>;</corresp></author-notes><pub-date pub-type="epub"><day>13</day><month>10</month><year>2015</year></pub-date><volume>05</volume><issue>12</issue><fpage>738</fpage><lpage>744</lpage><history><date date-type="received"><day>18</day>	<month>August</month>	<year>2015</year></date><date date-type="rev-recd"><day>accepted</day>	<month>17</month>	<year>October</year>	</date><date date-type="accepted"><day>20</day>	<month>October</month>	<year>2015</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p><html>
 <head></head>
 
  In this paper, we introduce Farey triangle graph 
  <img alt="" src="Edit_9ca08d34-d5e0-456e-864d-eb128ed8095f.jpg" />, Farey triangle matrix 
  <img alt="" src="Edit_12ef70ce-19cd-43f2-9b21-fe808707a6cb.jpg" />, complementary Farey triangle graph 
  <img alt="" src="Edit_b493f6b0-a763-4093-827e-6b4aa5c4349e.jpg" />and complementary Farey triangle matrix 
  <img alt="" src="Edit_0bad435c-9f15-4711-b18b-6fd35208f99a.jpg" />, and we derive some properties of the following matrices.
 
</html></p></abstract><kwd-group><kwd>Farey Triangle Graph</kwd><kwd> Farey Triangle Matrix</kwd><kwd> Complementary Farey Triangle Graph</kwd><kwd> Complementary Farey Triangle Matrix</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>A Farey sequence of order N is a set of irreducible fractions between 0 and 1 arranged in an increasing order, the denominators of which do not exceed N. <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x9.png" xlink:type="simple"/></inline-formula>could be obtained from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x10.png" xlink:type="simple"/></inline-formula> by calculating the mediant between two successive values from which it was derived. In [<xref ref-type="bibr" rid="scirp.60383-ref1">1</xref>] -[<xref ref-type="bibr" rid="scirp.60383-ref3">3</xref>] Farey graph and Farey matrix have been constructed from Farey sequence of order N. In [<xref ref-type="bibr" rid="scirp.60383-ref4">4</xref>] Farey partition is derived and discussed some matrix property from Farey sequence. In [<xref ref-type="bibr" rid="scirp.60383-ref5">5</xref>] Farey graph is introduced in iterative process. In this paper we construct Farey tri-</p><p>angle graph<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x11.png" xlink:type="simple"/></inline-formula>, in iterative process, and it is constructed from the method of mediant property as follows in the Farey sequence. From the co-ordinates of this graph we form a Farey triangle matrix<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x12.png" xlink:type="simple"/></inline-formula>. Similarly we construct complementary Farey triangle graph <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x13.png" xlink:type="simple"/></inline-formula> and complementary Farey triangle matrix<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x14.png" xlink:type="simple"/></inline-formula>.</p></sec><sec id="s2"><title>2. Farey Triangle Graph</title><sec id="s2_1"><title>2.1. Definition: Farey Triangle Graph: <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x15.png" xlink:type="simple"/></inline-formula></title><p>Farey triangle graph of order N is constructed from Farey Sequence. Consider X and Y axes with vertices as Farey Sequnence in<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x16.png" xlink:type="simple"/></inline-formula>. The Farey triangle graph of order N is formed from Farey triangle graph of order<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x17.png" xlink:type="simple"/></inline-formula>, iteratively as Farey sequence. In this graph, vertices from X to Y axis is joined only if the vertices (or Farey fractions) are same to obtain a Farey triangle.</p></sec><sec id="s2_2"><title>2.2. Construction of Farey Triangle Graph</title><p>The Farey triangle graph of order 1 begin with vertices <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x18.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x19.png" xlink:type="simple"/></inline-formula> in both axes. The vertex <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x20.png" xlink:type="simple"/></inline-formula> is the ori-</p><p>gin of the Farey triangle graph of order 1. In this graph join the vertices when X and Y axes have the same fractions to obtain a Farey triangle. <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x21.png" xlink:type="simple"/></inline-formula>is constructed from<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x21.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x22.png" xlink:type="simple"/></inline-formula>. In this graph the vertices are inserted by the method of the mediant between each pair of consecutive fractions in both axes of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x21.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x22.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x23.png" xlink:type="simple"/></inline-formula>. Si-</p><p>milarly, we follow the same method to obtain <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula> from<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula>. The Farey triangle graph <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula> of order N can be constructed from Farey triangle graph <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula> by using the Farey sum operation denoted as<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula>. In <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x29.png" xlink:type="simple"/></inline-formula> the vertices in X and Y axes are irreducible fractions in Farey sequence of order<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x29.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x30.png" xlink:type="simple"/></inline-formula>. For each edge in <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x29.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x30.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x31.png" xlink:type="simple"/></inline-formula> introduced in iteration<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x29.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x30.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x31.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x32.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x24.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x25.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x26.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x27.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x28.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x29.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x30.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x31.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x32.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x33.png" xlink:type="simple"/></inline-formula>could be obtained</p><p>from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x34.png" xlink:type="simple"/></inline-formula> by calculating the mediant between each pair of consecutive fractions in both axes of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x34.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x35.png" xlink:type="simple"/></inline-formula>. Some illustrations are presented below: Figures 1-4 denote the Farey triangle graph of different order, from this graph we define Farey triangle matrix.</p><p>In the above illustrations, the like coloured lines denote the edges inserted in successive iterations.</p><fig id="fig1"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref></label><caption><title> Farey triangle graph of order 1</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x36.png"/></fig><fig id="fig2"  position="float"><label><xref ref-type="fig" rid="fig2">Figure 2</xref></label><caption><title> Farey triangle graph of order 2</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x37.png"/></fig><fig id="fig3"  position="float"><label><xref ref-type="fig" rid="fig3">Figure 3</xref></label><caption><title> Farey triangle graph of order 3</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x38.png"/></fig><fig id="fig4"  position="float"><label><xref ref-type="fig" rid="fig4">Figure 4</xref></label><caption><title> Farey triangle graph of order 4</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x39.png"/></fig></sec><sec id="s2_3"><title>2.3. Farey Triangle Matrix</title><p>Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x40.png" xlink:type="simple"/></inline-formula> be a Farey triangle. The vertices of the triangle are clearly Farey fractions. Let the abscissa be <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x40.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x41.png" xlink:type="simple"/></inline-formula> and ordinate<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x40.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x41.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x42.png" xlink:type="simple"/></inline-formula>, we obtain</p><disp-formula id="scirp.60383-formula667"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x43.png"  xlink:type="simple"/></disp-formula><p>The Farey triangle graph forms a matrix [<xref ref-type="bibr" rid="scirp.60383-ref6">6</xref>] ,</p><disp-formula id="scirp.60383-formula668"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x44.png"  xlink:type="simple"/></disp-formula><p>where a and b are the numerator of Farey fractions and c denote the order of the Farey sequence. k denote the number of vertices inserted to move from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x45.png" xlink:type="simple"/></inline-formula> to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x45.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x46.png" xlink:type="simple"/></inline-formula>.</p>Illustrations<p>1) Farey triangle matrix of order 2.</p><disp-formula id="scirp.60383-formula669"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x47.png"  xlink:type="simple"/></disp-formula><p>2) Farey triangle matrix of order 3</p><p>Farey triangle graph of order 3 is derived from Farey triangle graph of order 2. Here two vertices are inserted, so two Farey triangle matrices are constructed.</p><disp-formula id="scirp.60383-formula670"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x48.png"  xlink:type="simple"/></disp-formula></sec><sec id="s2_4"><title>2.4. Theorem</title><p>The sum of the determinants of the Farey triangle matrices of prime order is given by</p><disp-formula id="scirp.60383-formula671"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x49.png"  xlink:type="simple"/></disp-formula><p>Proof:</p><p>In Farey triangle graph of prime order<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x50.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x50.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x51.png" xlink:type="simple"/></inline-formula>vertices are introduced.</p><p>The ordinates<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x52.png" xlink:type="simple"/></inline-formula>; <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x52.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x53.png" xlink:type="simple"/></inline-formula>are connected only if <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x52.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x53.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x54.png" xlink:type="simple"/></inline-formula> and it forms a matrix</p><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x55.png" xlink:type="simple"/></inline-formula>where</p><p>The sum of the determinant of these matrices is</p><disp-formula id="scirp.60383-formula672"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x57.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.60383-formula673"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x58.png"  xlink:type="simple"/></disp-formula></sec><sec id="s2_5"><title>2.5. Theorem</title><p>The sum of Farey triangle matrices of prime order is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x59.png" xlink:type="simple"/></inline-formula>.</p><p>Proof:</p><p>The Farey triangle matrices of prime order</p><disp-formula id="scirp.60383-formula674"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x60.png"  xlink:type="simple"/></disp-formula><p>where<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x61.png" xlink:type="simple"/></inline-formula>.</p><disp-formula id="scirp.60383-formula675"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x62.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.60383-formula676"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x63.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.60383-formula677"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x64.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.60383-formula678"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x65.png"  xlink:type="simple"/></disp-formula></sec></sec><sec id="s3"><title>3. Complementary Farey Triangle Graph</title><sec id="s3_1"><title>3.1. Definition</title><p>The complementary Farey triangle graph <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x66.png" xlink:type="simple"/></inline-formula> of order N is a Farey triangle with edges as the line joining vertices whose numerators are complementary with respect to the order of the graph and it forms complementary Farey triangle.</p></sec><sec id="s3_2"><title>3.2. Construction of Complementary Farey Triangle Graph</title><p>The complementary Farey triangle graph <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x67.png" xlink:type="simple"/></inline-formula> of order <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x67.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x68.png" xlink:type="simple"/></inline-formula> can be constructed from complementary Farey triangle graph<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x67.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x68.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x69.png" xlink:type="simple"/></inline-formula>. The vertices are inserted as in Farey triangle graph. In this graph the</p><p>vertices are connected if the sum of the numerators of the fractions in each vertices of X and Y axis is equal to the order of the complementary Farey triangle graph. In complementary Farey triangle graph of order 2, we be-</p><p>gin with vertices <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x70.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x70.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x71.png" xlink:type="simple"/></inline-formula> in both axes. The vertex <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x70.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x71.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x72.png" xlink:type="simple"/></inline-formula> is the origin of the complementary Farey</p><p>triangle graph. In this graph the vertices are inserted by the method of the mediant between each pair of consec-</p><p>utive fractions in both axes of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x73.png" xlink:type="simple"/></inline-formula>. We follow the same method to obtain <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x73.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x74.png" xlink:type="simple"/></inline-formula> from<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x73.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x74.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x75.png" xlink:type="simple"/></inline-formula>.</p><p>Figures 5-7 denotes the complementary Farey Triangle Graph of different orders, from this graph we define Complementary Farey Triangle Matrix. Some illustrations are presented below:</p></sec><sec id="s3_3"><title>3.3. Complementary Farey Triangle Matrix</title><p>The vertices of the complementary Farey triangle namely Farey fractions are used to construct this matrix. Let the abscissa be <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x76.png" xlink:type="simple"/></inline-formula> and ordinate<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x76.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x77.png" xlink:type="simple"/></inline-formula>. Join these vertices to form a complementary Farey triangle graph and correspondingly complementary Farey triangle matrix as given below.</p><fig id="fig5"  position="float"><label><xref ref-type="fig" rid="fig5">Figure 5</xref></label><caption><title> Complementary Farey triangle graph of order 2</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x78.png"/></fig><fig id="fig6"  position="float"><label><xref ref-type="fig" rid="fig6">Figure 6</xref></label><caption><title> Complementary Farey triangle graph of order 3</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x79.png"/></fig><fig id="fig7"  position="float"><label><xref ref-type="fig" rid="fig7">Figure 7</xref></label><caption><title> Complementary Farey triangle graph of order 4</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/3-5300963x80.png"/></fig><disp-formula id="scirp.60383-formula679"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x81.png"  xlink:type="simple"/></disp-formula><p>where a and b are the numerator of Farey fractions and c denote the order of the Farey sequence. k denote the number of vertices inserted to move from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x82.png" xlink:type="simple"/></inline-formula> to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x82.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x83.png" xlink:type="simple"/></inline-formula>.</p><sec id="s3_3_1"><title>3.3.1. Illustrations</title><p>1) Complementary Farey triangle matrix of order 2.</p><disp-formula id="scirp.60383-formula680"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x84.png"  xlink:type="simple"/></disp-formula><p>2) Complementary Farey triangle matrix of order 3</p><disp-formula id="scirp.60383-formula681"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x85.png"  xlink:type="simple"/></disp-formula></sec><sec id="s3_3_2"><title>3.3.2. Remark</title><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x86.png" xlink:type="simple"/></inline-formula>.</p></sec></sec><sec id="s3_4"><title>3.4. Theorem</title><p>The sum of determinants of the complementary Farey triangle matrices of prime order p is</p><disp-formula id="scirp.60383-formula682"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x87.png"  xlink:type="simple"/></disp-formula><p>Proof:</p><p>Consider the complementary Farey triangle matrices of prime order.</p><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x88.png" xlink:type="simple"/></inline-formula>;</p><p>where <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/3-5300963x90.png" xlink:type="simple"/></inline-formula></p><disp-formula id="scirp.60383-formula683"><graphic  xlink:href="http://html.scirp.org/file/3-5300963x91.png"  xlink:type="simple"/></disp-formula></sec></sec><sec id="s4"><title>Cite this paper</title><p>A.Gnanam,C.Dinesh, (2015) Farey Triangle Graphs and Farey Triangle Matrices. Advances in Pure Mathematics,05,738-744. doi: 10.4236/apm.2015.512067</p></sec></body><back><ref-list><title>References</title><ref id="scirp.60383-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">Redmond, D. (1996) Number Theory: An Introduction. Marcel Dekker, Inc., New York.</mixed-citation></ref><ref id="scirp.60383-ref2"><label>2</label><mixed-citation publication-type="other" xlink:type="simple">Gnanam, A., Gopalan, M.A. and Dinesh, C. (2015) Farey Matrix. International Journal of Mathematics Trends and Techonology, 19. http://dx.doi.org/10.14445/22315373/IJMTT-V19P501</mixed-citation></ref><ref id="scirp.60383-ref3"><label>3</label><mixed-citation publication-type="other" xlink:type="simple">Hardy, G.H. and Wright, E.M. (1975) An Introduction to the Theory of Numbers. 4th Edition, The Clarendon Press, Oxford.</mixed-citation></ref><ref id="scirp.60383-ref4"><label>4</label><mixed-citation publication-type="other" xlink:type="simple">Nogueria, A. and Sevennec, B. (2006) Multidimensional Farey Partitions. Indagationes Mathematicae, 17, 437-456.http://dx.doi.org/10.1016/S0019-3577(06)80043-1</mixed-citation></ref><ref id="scirp.60383-ref5"><label>5</label><mixed-citation publication-type="other" xlink:type="simple">Zhang, Z.Z., Wu, B. and Lin, Y. (2012) Counting Spanning Trees in a Small-World Farey Graph. Physica A: Statistical Mechanics and Its Applications, 391, 3342-3349. http://dx.doi.org/10.1016/j.physa.2012.01.039</mixed-citation></ref><ref id="scirp.60383-ref6"><label>6</label><mixed-citation publication-type="other" xlink:type="simple">Kwak, J.H. and Hong, S. (2010) Linear Algebra. Springer International Edition.</mixed-citation></ref></ref-list></back></article>