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%I #6 Dec 18 2015 18:17:39
%S 2,8,61,932,28310,1702795,202939372,47927020569,22429704522082,
%T 20801275290690832,38227523793468047029,139214024121151998219523,
%U 1004640378392088270863934462,14366768178214114259445967952070
%N Number of n X n symmetric binary matrices with each 1 adjacent to no more than 6 king-move neighboring 1s
%H R. H. Hardin, <a href="/A191482/b191482.txt">Table of n, a(n) for n = 1..18</a>
%e Some solutions for n=4
%e ..0..1..0..0....1..1..0..1....1..0..0..0....1..0..1..0....1..1..1..0
%e ..1..0..1..1....1..1..1..0....0..0..1..1....0..0..1..1....1..1..0..1
%e ..0..1..1..0....0..1..0..1....0..1..1..1....1..1..1..1....1..0..1..0
%e ..0..1..0..0....1..0..1..1....0..1..1..0....0..1..1..0....0..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jun 03 2011
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