%I A091438
%S A091438 1,1,2,1,2,3,1,3,4,5,1,3,6,7,7,1,4,8,12,12,11,1,4,10,16,21,19,15,1,5,12,
%T A091438 23,31,36,30,22,1,5,15,28,45,55,58,45,30,1,6,17,37,60,84,94,92,67,42,1,
%U A091438 6,20,44,80,115,147,153,140,97,56,1,7,23,55,101,161,211,249,244
%N A091438 Triangle a(n,k) of partitions of n objects of 2 colors, k of which are
black and each part with at least one black object.
%C A091438 Number of ways to factor p^(n-k)*q^k where p and q are distinct primes
and each factor is a multiple of q.
%F A091438 G.f.: A(x, y) = prod{i=1..inf, j=1..i}(1/(1-x^i*y^j))
%e A091438 1; 1,2; 1,2,3; 1,3,4,5; 1,3,6,7,7; ...
%Y A091438 Row sums: A000219. Main diagonal: A000041. Cf. A060243.
%Y A091438 Sequence in context: A066010 A109974 A026820 this_sequence A011794 A073300
A104468
%Y A091438 Adjacent sequences: A091435 A091436 A091437 this_sequence A091439 A091440
A091441
%K A091438 nonn,tabl
%O A091438 1,3
%A A091438 Wouter Meeussen (wouter.meeussen(AT)pandora.be) and Christian G. Bower
(bowerc(AT)usa.net), Jan 08 2004
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