This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A115792 #17 Jul 17 2025 09:42:32
%S A115792 0,0,1,1,2,3,6,11,20,37,69,126,232,426,784,1442,2652,4878,8973,16503,
%T A115792 30354,55829,102686,188869,347384,638939,1175193,2161516,3975648,
%U A115792 7312356,13449520,24737524,45499400,83686444,153923369,283109213,520719026,957751607
%N A115792 a(n) = ceiling(g(A000073(n))) with g(k) = (k-1)^2/(4k).
%C A115792 Old name: A dihedral D1 elliptical transform on A000073.
%C A115792 A D1 elliptical invariant transform leaves the ratio unchanged.
%F A115792 Conjectures from _Chai Wah Wu_, Dec 21 2023: (Start)
%F A115792 a(n) = a(n-2) + 2*a(n-3) + 2*a(n-4) + 2*a(n-5) + 2*a(n-6) + 2*a(n-7) + 3*a(n-8) + 2*a(n-9) + a(n-10) for n > 11.
%F A115792 G.f.: x^4*(-x^2 - x - 1)/((x + 1)*(x^2 + 1)*(x^4 + 1)*(x^3 + x^2 + x - 1)). (End)
%F A115792 For n >= 5, a(n) = a(n-1) + a(n-2) + a(n-3) - A132151(n+2). - _Peter Munn_, Jul 17 2025
%t A115792 g[x_] = (x - 1)^2/(-4*x) M = {{0, 1, 0}, {0, 0, 1}, {1, 1, 1}} w[0] = {0, 1, 1}; w[n_] := w[n] = M.w[n - 1] a0 = Table[ -Floor[g[w[n][[1]]]], {n, 1, 25}] b0 = Table[N[a0[[n + 1]]/a0[[n]]], {n, 2, 24}]
%Y A115792 Cf. A000073, A132151.
%K A115792 nonn,easy
%O A115792 2,5
%A A115792 _Roger L. Bagula_, Mar 13 2006
%E A115792 Edited by _Peter Munn_, Jul 17 2025