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%I #4 Mar 31 2012 12:35:41
%S 0,0,352128,28021865662196736,82386976561127733213714195200,
%T 6159222400147050126331043386857585651398400,
%U 8076571943273575432916626559495058426486672272842882658769
%N Number of 3*n X n 0..3 arrays with row sums 7 and column sums 21
%H R. H. Hardin, <a href="/A172765/b172765.txt">Table of n, a(n) for n=1..10</a>
%K nonn
%O 1,3
%A _R. H. Hardin_ Feb 06 2010