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%I #24 Feb 19 2024 10:28:28
%S 1,3,14,52,60,130,184,656,5472,8648,12008,34688,2118656,2500704,
%T 33721216,40575616,59376256,89397016,99523456,134438912,150441856,
%U 173706136,283417216,537346048,1082640256,6801628304,91707741184
%N Numbers k that divide sigma(k) + d(k), where d(k) is the number of divisors of k and sigma(k) is their sum.
%C a(28) > 2*10^11. 14451706793984, 2258918614925312 and 9007202811510784 are also terms. - _Donovan Johnson_, Feb 10 2012
%C a(28) > 10^13. - _Giovanni Resta_, Nov 13 2019
%t Do[If[Mod[DivisorSigma[1,n]+DivisorSigma[0,n],n]==0,Print[n]],{n,1,10^8}]
%o (PARI) for(n=1,10^8, if(Mod((sigma(n)+numdiv(n)), n)==0,print(n)))
%Y Cf. A000203, A000005.
%K nonn
%O 1,2
%A _Robert G. Wilson v_, Jul 26 2000
%E Corrected by _Jason Earls_, Aug 06 2001
%E Corrected by _T. D. Noe_, Nov 01 2006
%E a(25)-a(27) from _Donovan Johnson_, Dec 07 2008
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