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A284909 a(n) = A000041(A000009(n)).

%I A284909 #9 Apr 07 2017 01:36:13
%S A284909 1,1,1,2,2,3,5,7,11,22,42,77,176,385,1002,3010,8349,26015,105558,
%T A284909 386155,1741630,9289091,49995925,304801365,2291320912,18440293320,
%U A284909 172389800255,1987276856363,25025873760111,365749566870782,6965850144195831,144117936527873832
%N A284909 a(n) = A000041(A000009(n)).
%H A284909 Alois P. Heinz, <a href="/A284909/b284909.txt">Table of n, a(n) for n = 0..100</a>
%p A284909 with(numtheory):
%p A284909 b:= proc(n) option remember; `if`(n=0, 1, add(add(
%p A284909      `if`(d::odd, d, 0), d=divisors(j))*b(n-j), j=1..n)/n)
%p A284909     end:
%p A284909 a:= n-> combinat[numbpart](b(n)):
%p A284909 seq(a(n), n=0..35);
%t A284909 Table[PartitionsP@ PartitionsQ@ n, {n,0, 50}] (* _Indranil Ghosh_, Apr 07 2017 *)
%Y A284909 Cf. A000009, A000041, A058699, A284908, A284910.
%K A284909 nonn
%O A284909 0,4
%A A284909 _Alois P. Heinz_, Apr 05 2017