%I A058408
%S A058408 1,4,26,129,546,2010,6615,19650,53790,137035,328262,745078,1613072,
%T A058408 3348198,6693822,12937656,24253200,44219610,78604130,136511100,
%U A058408 232054284
%N A058408 Number of 3 X n nonnegative integer matrices with all column sums 4, 
               up to row and column permutation.
%C A058408 Number of 3 X n nonnegative integer matrices with all column sums equal 
               to m, up to row and column permutation, is coefficient of x^n in 
               expansion of 1 / 6 * (1 / (1 - x)^C(m + 2,2) + 3 / (1 - x)^floor((m 
               + 2) / 2) / (1 - x^2)^(C(m + 2,2) - floor((m + 2) / 2)) / 2 + 2 / 
               (1 - x)^(C(m + 2,2) - 3 * floor(C(m + 2,2) / 3)) / (1 - x^3)^floor(C(m 
               + 2,2) / 3)).
%H A058408 <a href="a58407.pdf">Number of m x l nonnegative integer matrices with 
               all column sums equal to n, up to row and column permutation</a>
%F A058408 G.f.: 1/6*(1/(1-x)^15+3/(1-x)^3/(1-x^2)^6+2/(1-x^3)^5).
%Y A058408 Cf. A050531, A058389, A058407.
%Y A058408 Sequence in context: A101166 A140804 A147621 this_sequence A053906 A100236 
               A144068
%Y A058408 Adjacent sequences: A058405 A058406 A058407 this_sequence A058409 A058410 
               A058411
%K A058408 easy,nonn
%O A058408 0,2
%A A058408 Vladeta Jovovic (vladeta(AT)eunet.rs), Nov 25 2000