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%I #10 Apr 07 2020 15:38:38
%S 1,1,9,215,13825,1865715,472211360,205617134345,144413237202513,
%T 155491132440121969,246331815235550280739,555051611796729847585857,
%U 1728979263188082473586904451,7267279122553798970928760164349,40366145202716102133415620482175732,290962702320861139000003963988839815695
%N Number of (8*n) X n binary arrays with rows in nonincreasing order, 8 ones in every column and no more than 2 ones in any row.
%C Number of n X n symmetric matrices with nonnegative integer entries and all row and column sums 8. - _Andrew Howroyd_, Apr 07 2020
%e All solutions for 16X2
%e ..1..1....1..1....1..1....1..1....1..1....1..1....1..1....1..0....1..1
%e ..1..1....1..1....1..1....1..0....1..1....1..1....1..1....1..0....1..1
%e ..1..1....1..1....1..1....1..0....1..1....1..0....1..1....1..0....1..1
%e ..1..1....1..1....1..1....1..0....1..1....1..0....1..1....1..0....1..0
%e ..1..1....1..1....1..1....1..0....1..1....1..0....1..0....1..0....1..0
%e ..1..0....1..1....1..1....1..0....1..1....1..0....1..0....1..0....1..0
%e ..1..0....1..0....1..1....1..0....1..1....1..0....1..0....1..0....1..0
%e ..1..0....1..0....1..0....1..0....1..1....1..0....1..0....1..0....1..0
%e ..0..1....0..1....0..1....0..1....0..0....0..1....0..1....0..1....0..1
%e ..0..1....0..1....0..0....0..1....0..0....0..1....0..1....0..1....0..1
%e ..0..1....0..0....0..0....0..1....0..0....0..1....0..1....0..1....0..1
%e ..0..0....0..0....0..0....0..1....0..0....0..1....0..1....0..1....0..1
%e ..0..0....0..0....0..0....0..1....0..0....0..1....0..0....0..1....0..1
%e ..0..0....0..0....0..0....0..1....0..0....0..1....0..0....0..1....0..0
%e ..0..0....0..0....0..0....0..1....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..1....0..0
%Y Row 8 of A188403.
%K nonn
%O 0,3
%A _R. H. Hardin_, Mar 30 2011
%E a(0)=1 prepended and terms a(9) and beyond from _Andrew Howroyd_, Apr 06 2020
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