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A366110 a(n) is the difference between the maximum and minimum number whose proper divisors sum to n, or 0 if there is no such number.

%I A366110 #53 Oct 28 2023 14:19:44
%S A366110 0,0,0,0,19,0,39,0,0,0,0,8,147,17,14,16,0,12,327,73,18,28,0,48,0,64,0,
%T A366110 72,0,189,903,202,0,160,0,168,0,0,37,328,1651,387,1767,280,34,364,0,
%U A366110 476,54,448,0,432,2767,677,0,604,0,432,0,528,3603,753,66,826,0,768,0,720,0
%N A366110 a(n) is the difference between the maximum and minimum number whose proper divisors sum to n, or 0 if there is no such number.
%C A366110 A152454 is the irregular triangle in which row n lists the numbers whose proper divisors sum to n.
%H A366110 Michel Marcus, <a href="/A366110/b366110.txt">Table of n, a(n) for n = 2..10001</a>
%F A366110 a(n) = A135244(n) - A070015(n).
%F A366110 a(A005114(n)) = a(A057709(n)) = 0.
%e A366110 A152454 begins as []; [4]; [9]; []; [6, 25]; [8]; [10, 49]...
%e A366110 so sequence begins 0, 0, 0, 0, 19, 0, 39, ...
%o A366110 (PARI) lista(nn) = my(v = vector(nn, k, [])); forcomposite (i=1, nn^2, my(x=sigma(i)-i); if (x <=  nn, v[x] = concat(v[x], i));); vector(nn-1, k, k++; if (#v[k], vecmax(v[k]) - vecmin(v[k])));
%Y A366110 Cf. A001065, A152454.
%Y A366110 Cf. A070015, A135244.
%Y A366110 Cf. A005114, A057709.
%K A366110 nonn
%O A366110 2,5
%A A366110 _Michel Marcus_, Oct 28 2023