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%I #26 Dec 07 2017 15:50:03
%S 860,5336,6536,9656,16256,55796,70864,98048,361556,776096,2227616,
%T 4145216,4498136,4632896,8124416,13086016,34869056,38546576,150094976,
%U 172960856,196066256,962085536,1080008576,1733780336,2143256576,9677743616,11276687456,21568135616
%N Numbers n whose abundance is 128: sigma(n) - 2n = 128.
%t fQ[n_] := DivisorSigma[1, n] == 2 n + 128; Select[ Range@ 10^8, fQ] (* _Robert G. Wilson v_, Nov 19 2017 *)
%o (PARI) isok(n) = sigma(n) - 2*n == 128; \\ _Michel Marcus_, Sep 20 2017
%Y Cf. A088831, A088832, A088833, A141547, A175989, A275996.
%Y Subsequence of A259174.
%K nonn
%O 1,1
%A _Fabian Schneider_, Sep 20 2017
%E a(9)-a(18) from _Michel Marcus_, Sep 20 2017
%E a(19)-a(28) from _Robert G. Wilson v_, Nov 20 2017
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