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%I #18 Dec 15 2017 17:35:53
%S 28,652,10828
%N Numbers n such that the sum of its aliquot parts and the number of its divisors are both perfect numbers.
%C Subsequence of A237286. - _Roderick MacPhee_, Jan 19 2017
%t p = {6, 28, 496, 8128, 33550336}; Do[a = Divisors[n]; If[ Position[p, Plus @@ Drop[a, -1]] != {} && Position[p, Length[a]] != {}, Print[n]], {n, 1, 10^7}]
%o (PARI) {for(n=1,10^8,d=numdiv(n); if(d==sigma(d)-d,s=sigma(n)-n; if(s==sigma(s)-s,print1(n,","))))}
%Y Cf. A000396, A001065, A000005.
%K more,nonn,bref
%O 1,1
%A _Jason Earls_, May 10 2002
%E Edited by _Robert G. Wilson v_, May 14 2002
%E No further terms below 10^8. Is the sequence complete? - _Klaus Brockhaus_, May 17 2002
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