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 A387350 #5 Sep 01 2025 22:08:24 %S A387350 2,5,10,13,15,18,23,26,28,31,34,36,39,44,47,49,52,57,60,65,68,70,73, %T A387350 78,81,83,86,89,91,94,99,102,104,107,112,115,120,123,125,128,133,136, %U A387350 138,141,146,149,154,157,159,162,167,170,172,175,178,180,183,188 %N A387350 Positions of 1's in A387348. %C A387350 This sequence together with A387349 and A387351 partition the positive integers. %C A387350 Conjecture: the difference sequence, (3, 5, 3, 2, 3, 5, 3, 2, 3, 3, 2, 3, 5, 3, 2, 3, 5, 3, 5, ... ) has exactly 3 distinct terms. %t A387350 z = 300; %t A387350 A[n_, k_] := Module[{t, a, b}, t = (1 + Sqrt[5])/2; %t A387350 a = Floor[n*(t + 1) + 1 + t/2]; b = Round[a*t]; ({b, a} . MatrixPower[{{1, 1}, {1, 0}}, k])[[2]]]; %t A387350 ts = Table[A[n, k], {n, 0, z - 1}, {k, 0, z - 1}]; (* A035506, Stolarsky array *) %t A387350 W[n_, k_] := Fibonacci[k + 1] Floor[n*GoldenRatio] + (n - 1) Fibonacci[k]; %t A387350 tw = Table[W[n, k], {n, 1, z}, {k, 1, z}]; (* A035513, Wythoff array *) %t A387350 diff = tw - ts; %t A387350 u = Table[diff[[n]][[2]], {n, 1, z}] %t A387350 Flatten[Position[u, 0]] (* A387349 *) %t A387350 Flatten[Position[u, 1]] (* A387350 *) %t A387350 Flatten[Position[u, -1]] (* A387351 *) %Y A387350 Cf. A387348, A387349, A387351. %K A387350 nonn,new %O A387350 1,1 %A A387350 _Clark Kimberling_, Aug 27 2025