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Multiply-perfect numbers k that have a divisor d such that sigma(d)*d = k.
2

%I #14 Sep 29 2021 04:47:40

%S 1,6,28,120,496,672,8128,30240,32760,523776,23569920,33550336,

%T 142990848,1379454720,8589869056,66433720320,137438691328,

%U 153003540480,403031236608,14942123276641920,275502900594021408,2305843008139952128,71065075104190073088,154345556085770649600,203820700083634254643200,34384125938411324962897920

%N Multiply-perfect numbers k that have a divisor d such that sigma(d)*d = k.

%C Multiply-perfect numbers (A007691) that are present in A064987.

%C Note how the first three terms of A005820 are included here, while the next three are in A348032.

%C At least the even terms of A000396 are all present.

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%Y Intersection of A007691 and A327165.

%Y Cf. A000396, A005820, A064987, A348032 (complement in A007691), A348035 (subsequence).

%K nonn

%O 1,2

%A _Antti Karttunen_, Sep 26 2021