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A292626
Numbers n whose abundance is 128: sigma(n) - 2n = 128.
0
860, 5336, 6536, 9656, 16256, 55796, 70864, 98048, 361556, 776096, 2227616, 4145216, 4498136, 4632896, 8124416, 13086016, 34869056, 38546576, 150094976, 172960856, 196066256, 962085536, 1080008576, 1733780336, 2143256576, 9677743616, 11276687456, 21568135616
OFFSET
1,1
MATHEMATICA
fQ[n_] := DivisorSigma[1, n] == 2 n + 128; Select[ Range@ 10^8, fQ] (* Robert G. Wilson v, Nov 19 2017 *)
PROG
(PARI) isok(n) = sigma(n) - 2*n == 128; \\ Michel Marcus, Sep 20 2017
CROSSREFS
Subsequence of A259174.
Sequence in context: A108822 A278156 A249461 * A115749 A105323 A206756
KEYWORD
nonn
AUTHOR
Fabian Schneider, Sep 20 2017
EXTENSIONS
a(9)-a(18) from Michel Marcus, Sep 20 2017
a(19)-a(28) from Robert G. Wilson v, Nov 20 2017
STATUS
approved