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A362135 Indices of novel terms in A360179.

%I A362135 #8 Apr 14 2023 11:35:46
%S A362135 1,3,5,7,9,12,15,17,21,25,29,31,36,41,47,52,58,64,69,74,82,87,92,100,
%T A362135 106,112,120,128,138,145,153,160,168,176,183,189,198,209,220,233,242,
%U A362135 252,265,277,285,294,309,325,338,349,359,371,384,400,413,430,447,459,474,492,515,533,545,557,570,594
%N A362135 Indices of novel terms in A360179.
%C A362135 If we read A360179 as an irregular triangle of rows whose terms strictly increase, then a(n) is the index k such that A360179(k) is the last and largest term in row n.
%C A362135 A362128 is a subsequence of this sequence.
%H A362135 Michael De Vlieger, <a href="/A362135/b362135.txt">Table of n, a(n) for n = 1..58188</a>
%t A362135 nn = 600;
%t A362135 c[_] := False; h[_] := 0; f[n_] := DivisorSigma[0, n];
%t A362135 a[1] = j = u = w = 1;
%t A362135 {1}~Join~Rest@ Reap[Do[
%t A362135       If[c[j],
%t A362135         k = j + f[u]; h[j]++; h[u]--,
%t A362135         k = f[j]; c[j] = True; h[j]++; Sow[n - 1] ];
%t A362135       u = Min[u, j]; Set[{a[n], q[k], j}, {k, True, k}];
%t A362135       While[h[u] == 0, u++], {n, 2, nn}] ][[-1, -1]]
%Y A362135 Cf. A360179, A362128, A362134.
%K A362135 nonn
%O A362135 1,2
%A A362135 _Michael De Vlieger_, Apr 10 2023