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 A050173 #17 Jul 04 2021 15:34:36
%S A050173 4,7,10,12,15,17,19,20,23,26,28,29,32,35,37,38,41,43,44,47,50,52,53,
%T A050173 56,58,60,61,64,66,67,69,70,73,76,78,80,81,84,87,89,90,93,95,97,98,
%U A050173 100,102,103,105,108,111,113,114,116,119,121,124
%N A050173 Numbers k such that A050170(k) > A050170(k+1).
%C A050173 Complement of A050172.
%H A050173 Ivan Neretin, <a href="/A050173/b050173.txt">Table of n, a(n) for n = 1..10000</a>
%t A050173 kmax = 124; (* b = A050170 *) b[1] = 1; b[n_] := b[n] = If[FreeQ[Join[{0}, Array[b, n - 1]], f = Floor[b[n - 1]/Sqrt[5]]], f, Floor[b[n - 1]*Sqrt[5]]]; Reap[For[k = 1, k <= kmax, k++, If[b[k] > b[k + 1], Sow[k]]]][[2, 1]] (* _Jean-François Alcover_, Sep 12 2017 *)
%Y A050173 Cf. A050170, A050172.
%K A050173 nonn
%O A050173 1,1
%A A050173 _Clark Kimberling_