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A331640 Number of binary matrices with n columns and any number of distinct nonzero rows with 2 ones in every column. 3

%I

%S 1,0,6,120,6174,449520,49686726,7455901320,1479839874414,

%T 373573957133280,117097298726892246,44596327028174342520,

%U 20287402287658565190654,10864410524883717498300240,6765647366010527963979060966,4847736403559133115838948559720

%N Number of binary matrices with n columns and any number of distinct nonzero rows with 2 ones in every column.

%H Andrew Howroyd, <a href="/A331640/b331640.txt">Table of n, a(n) for n = 0..200</a>

%e The a(2) = 6 matrices are:

%e [1 1] [1 1] [1 0] [1 0] [0 1] [0 1]

%e [1 0] [0 1] [1 1] [0 1] [1 1] [1 0]

%e [0 1] [1 0] [0 1] [1 1] [1 0] [1 1]

%Y Row n=2 of A331567.

%Y Cf. A331641.

%K nonn

%O 0,3

%A _Andrew Howroyd_, Jan 23 2020

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Last modified January 24 00:05 EST 2022. Contains 350515 sequences. (Running on oeis4.)