%I #35 May 24 2018 15:58:33
%S 1,7,132,6178,594203,85820809,16341829155,3875736708590,
%T 1112175913348040,378860991866916370,151006214911844288232,
%U 69600017255860985666964,36729204987785981237238642,22003003913198378660826731007,14851323097928973689736994569534
%N Number of nonisomorphic binary n X n matrices with four 1's per column under row and column permutations.
%H Andrew Howroyd, <a href="/A247597/b247597.txt">Table of n, a(n) for n = 4..40</a>
%H StackExchange, <a href="http://math.stackexchange.com/questions/616834/">How many arrays with crossed cells, order of rows/columns irrelevant</a>, Dec 13 2013
%p seq(matrix_marks(n,4), n=3..15); # Using the uploaded program to A247417
%o (PARI) \\ See A304942 for Blocks
%o a(n) = Blocks(n, n, 4); \\ _Andrew Howroyd_, May 24 2018
%Y Column k=4 of A304942.
%Y Cf. A247417, A247596, A247598.
%K nonn
%O 4,2
%A _Marko Riedel_, Sep 21 2014
%E Terms a(16) and beyond from _Andrew Howroyd_, May 24 2018
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