|
%I #8 Dec 08 2015 03:19:31
%S 0,0,0,0,0,0,6,11,35,47,57,16,0,98,187,146,176,184,525,326,1525,1007,
%T 254,1632,1275,4261,3311,2859,1476,7489,4383,4408,7624,9859,7450,0,
%U 5428,9086,38472,50191,29898,33867,41264,22030,47947,109323,107783,77168
%N Sum of proper divisors minus the number of proper divisors of the number of partitions of n, A000041(n).
%C 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 a(n) = A001065(A000041(n)) - A032741(A000041(n)) = A152770(A000041(n)).
%p 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 Cf. A000005, A000041, A000203, A001065, A002808, A008578, A032741, A152770.
%K easy,nonn
%O 1,7
%A _Omar E. Pol_, Dec 21 2008
%E More terms from _R. J. Mathar_, Jan 22 2009
|
