%I #5 Jan 24 2020 07:51:24
%S 1,4,14,89,542,5156,47294,570074,7103343,104493608,1622632574,
%T 28411638982,526858348382,10699857854372,230297862127828,
%U 5330284144906443,130370767029135902,3390229775073259800,92801587319328411134,2679531116538955252338
%N Number of binary matrices with nonzero rows, a total of n ones and each column with the same number of ones.
%F a(n) = Sum_{dn} A262809(n/d, d).
%e The a(2) = 4 matrices are:
%e [1] [1 0] [0 1] [1 1]
%e [1] [0 1] [1 0]
%Y Cf. A262809.
%K nonn
%O 1,2
%A _Andrew Howroyd_, Jan 23 2020
