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A356445 a(n) is the number of times that A064440(n) occurs as the sum of proper divisors function (A001065).

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%I A356445 #35 Sep 24 2022 07:14:51
%S A356445 2,3,5,7,13,17,19,23,31,41,59,61,67,79,83,97,101,109,113,127,131,139,
%T A356445 149,151,193,199,223,227,229,277,283,317,397,433,521,541,577,607,677,
%U A356445 743,757,811,863,881,911,971,1031,1049,1063,1093,1249,1319,1373,1433,1489
%N A356445 a(n) is the number of times that A064440(n) occurs as the sum of proper divisors function (A001065).
%C A356445 The record values correspond to the terms of A064440.
%C A356445 All the terms are primes by definition.
%H A356445 Amiram Eldar, <a href="/A356445/b356445.txt">Table of n, a(n) for n = 1..188</a>
%F A356445 a(n) = A048138(A064440(n)).
%t A356445 seq[max_] := Module[{s = Table[0, {n, 1, max}], i, v = {}, m = 0}, Do[If[(i = DivisorSigma[1, n] - n) <= max, s[[i]]++], {n, 2, (max - 1)^2}]; Do[If[s[[i]] > m && PrimeQ[s[[i]]], m = s[[i]]; AppendTo[v, s[[i]]]], {i, 1, max}]; v]; seq[2000]
%Y A356445 Cf. A001065, A048138, A064440, A238895, A238896.
%K A356445 nonn
%O A356445 1,1
%A A356445 _Amiram Eldar_, Sep 23 2022