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%I #8 Apr 07 2020 14:53:41
%S 1,764,213798,22262244,1158207312,36218801244,767013376954,
%T 11930327925108,144413237202513,1419823497519000,11712930348839580,
%U 83160597646878696,518506187445244096,2885792129983693112,14530215365239964244,66929085400566337832,284683656715082259137
%N Number of (8*n) X 8 binary arrays with rows in nonincreasing order, n ones in every column and no more than 2 ones in any row.
%C Number of 8 X 8 symmetric matrices with nonnegative integer entries and all row and column sums n. - _Andrew Howroyd_, Apr 07 2020
%e Some solutions for 16X8
%e ..1..0..0..0..1..0..0..0....1..0..1..0..0..0..0..0....1..0..0..0..0..0..0..0
%e ..1..0..0..0..1..0..0..0....1..0..0..1..0..0..0..0....1..0..0..0..0..0..0..0
%e ..0..1..1..0..0..0..0..0....0..1..0..0..0..1..0..0....0..1..1..0..0..0..0..0
%e ..0..1..0..0..0..0..1..0....0..1..0..0..0..0..0..0....0..1..0..0..0..0..0..0
%e ..0..0..1..0..0..1..0..0....0..0..1..0..1..0..0..0....0..0..1..0..0..0..0..0
%e ..0..0..0..1..0..0..1..0....0..0..0..1..0..0..0..0....0..0..0..1..0..0..0..1
%e ..0..0..0..1..0..0..0..0....0..0..0..0..1..0..1..0....0..0..0..1..0..0..0..0
%e ..0..0..0..0..0..1..0..0....0..0..0..0..0..1..0..1....0..0..0..0..1..0..1..0
%e ..0..0..0..0..0..0..0..1....0..0..0..0..0..0..1..0....0..0..0..0..1..0..0..1
%e ..0..0..0..0..0..0..0..1....0..0..0..0..0..0..0..1....0..0..0..0..0..1..1..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..1..0..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
%Y Column 8 of A188403.
%K nonn
%O 0,2
%A _R. H. Hardin_, Mar 30 2011
%E a(0)=1 prepended and terms a(9) and beyond from _Andrew Howroyd_, Apr 07 2020
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