%I #7 Mar 09 2015 04:31:49
%S 1,3,28,905,103126,43437282,66141208960,385335180349569,
%T 8212830157184175946,683805150345009276656138,
%U 209730232681034628698652412600,254785524744054762580308183579130562
%N Half the number of n X n binary matrices having equal row sums.
%H R. H. Hardin, Jul 28 2008, <a href="/A140990/b140990.txt">Table of n, a(n) for n = 1..25</a>
%K nonn
%O 1,2
%A _R. H. Hardin_, Jul 28 2008
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