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A327945 Nonunitary pseudoperfect numbers: numbers that are equal to the sum of a subset of their nonunitary divisors.

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%I A327945 #11 Jul 13 2021 19:43:34
%S A327945 24,36,48,72,80,96,108,112,120,144,160,168,180,192,200,216,224,240,
%T A327945 252,264,288,300,312,320,324,336,352,360,384,392,396,400,408,416,432,
%U A327945 448,456,468,480,504,528,540,552,560,576,588,600,612,624,640,648,672,684
%N A327945 Nonunitary pseudoperfect numbers: numbers that are equal to the sum of a subset of their nonunitary divisors.
%C A327945 The nonunitary version of A005835.
%H A327945 Amiram Eldar, <a href="/A327945/b327945.txt">Table of n, a(n) for n = 1..10000</a>
%e A327945 36 is in the sequence since its nonunitary divisors are 2, 3, 6, 12, 18 and 36 = 6 + 12 + 18.
%t A327945 nudiv[n_] := Module[{d = Divisors[n]}, Select[d, GCD[#, n/#] > 1 &]]; s = {}; Do[d = nudiv[n]; If[Total[d] < n, Continue[]]; c = SeriesCoefficient[Series[Product[1 + x^d[[i]], {i, Length[d]}], {x, 0, n}], n]; If[c > 0, AppendTo[s, n]], {n, 1, 700}]; s
%Y A327945 Supersequence of A064591.
%Y A327945 Cf. A005835, A064597, A293188, A292985, A306983.
%K A327945 nonn
%O A327945 1,1
%A A327945 _Amiram Eldar_, Sep 30 2019