This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A014529 Largest convex area that can be tiled with n equilateral triangles whose sides s_k are relatively prime, i.e., gcd(s_1,...,s_n) = 1. 6
 1, 2, 3, 7, 11, 20, 36, 71, 146, 260, 495, 860, 1559, 2831, 5114 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The terms published to date (n <= 15) are consistent with a tribonacci growth rate. Specifically, floor(A000073(n+2) * 5/6) <= a(n) <= A000073(n+2). - Peter Munn, Sep 27 2017 a(16) is at least 9322. - Peter Munn, Feb 20 2018 REFERENCES Robert T. Wainwright, quoted by Ian Stewart, Math. Recreations, Scientific American, Jul 15 1997, p. 96. LINKS Hugo Pfoertner, Illustrations of configurations for n <= 11 Hugo Pfoertner, Illustration of configuration for n = 12, based on personal communication from Peter Munn Hugo Pfoertner, Illustration of configuration for n = 13, based on data in A289944 from Peter Munn Rainer Rosenthal, Illustration of configuration for n = 14, based on description in A289944 from Peter Munn Rainer Rosenthal, Illustration of configuration for n = 15, based on description in A289944 from Peter Munn Ian Stewart, Die unscheinbare Schwester der goldenen Zahl, Spektrum der Wissenschaft, Dossier 02/2003: Mathematische Unterhaltungen II, 55-57. EXAMPLE From Peter Kagey, Jul 31 2017: (Start) For n = 6 a convex polygon with area 20 is:       *-------*      / \     / \     /   \   /   \    /     \ /     \   *---*---*       \    \ / \ /         \     *---*-----------* The sides are relatively prime because gcd(1, 1, 1, 2, 2, 3) = 1. (End) CROSSREFS Cf. A000073, A089047, A133044, A289944. Sequence in context: A245738 A265093 A133044 * A095015 A024367 A232432 Adjacent sequences:  A014526 A014527 A014528 * A014530 A014531 A014532 KEYWORD nonn,hard,nice,more AUTHOR EXTENSIONS Terms a(12)-a(15) from John W. Layman STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 24 01:22 EDT 2018. Contains 311819 sequences. (Running on oeis4.)