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%I #7 Jan 25 2020 02:23:49
%S 1,2,4,11,16,55,64,418,440,4810,1024,99519,4096,1711115,2797136,
%T 43103893,65536,1877466431,262144,38795757791,236478538994,
%U 1291635643049,4194304,161575200818279,585914511112,2019395442729961,62318195369999169,119726874231250951,268435456
%N Number of binary matrices with distinct nonzero rows, a total of n ones and each column with the same number of ones and columns in nonincreasing lexicographic order.
%C The condition that the columns be in nonincreasing order is equivalent to considering nonequivalent matrices up to permutation of columns.
%F a(n) = Sum_{d|n} A331571(n/d, d).
%e The a(4) = 11 matrices are:
%e [1 0 0 0] [1 1] [1 0] [1 0] [1 1 0 0] [1 0 0 0]
%e [0 1 0 0] [1 0] [1 1] [0 1] [0 0 1 0] [0 1 1 0]
%e [0 0 1 0] [0 1] [0 1] [1 1] [0 0 0 1] [0 0 0 1]
%e [0 0 0 1]
%e .
%e [1 0 0 0] [1 1 1 0] [1 1 0 0] [1 0 0 0] [1 1 1 1]
%e [0 1 0 0] [0 0 0 1] [0 0 1 1] [0 1 1 1]
%e [0 0 1 1]
%Y Cf. A331571.
%K nonn
%O 1,2
%A _Andrew Howroyd_, Jan 24 2020
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