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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A152987 Sum of proper divisors minus the number of proper divisors of the number of partitions of n, A000041(n).

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%I A152987 #8 Dec 08 2015 03:19:31
%S A152987 0,0,0,0,0,0,6,11,35,47,57,16,0,98,187,146,176,184,525,326,1525,1007,
%T A152987 254,1632,1275,4261,3311,2859,1476,7489,4383,4408,7624,9859,7450,0,
%U A152987 5428,9086,38472,50191,29898,33867,41264,22030,47947,109323,107783,77168
%N A152987 Sum of proper divisors minus the number of proper divisors of the number of partitions of n, A000041(n).
%C A152987 Note that if a(n) != 0 then the number of partitions of n (A000041(n)) is a composite number (A002808), otherwise A000041(n) is a noncomposite number (A008578). See A152770.
%F A152987 a(n) = A001065(A000041(n)) - A032741(A000041(n)) = A152770(A000041(n)).
%p A152987 A000041 := proc(n) combinat[numbpart](n) ; end: A001065 := proc(n) numtheory[sigma](n)-n ; end: A032741 := proc(n) if n = 0 then 0; else numtheory[tau](n)-1 ; fi; end: A152987 := proc(n) local np ; np := A000041(n) ; A001065(np)-A032741(np) ; end: for n from 1 to 80 do printf("%d,",A152987(n)) ; end: # _R. J. Mathar_, Jan 22 2009
%Y A152987 Cf. A000005, A000041, A000203, A001065, A002808, A008578, A032741, A152770.
%K A152987 easy,nonn
%O A152987 1,7
%A A152987 _Omar E. Pol_, Dec 21 2008
%E A152987 More terms from _R. J. Mathar_, Jan 22 2009