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%I #5 Dec 18 2015 18:18:51
%S 1,8,129,4989,470170,109584463,63213422873,90394294712339,
%T 320691260884992280,2823496298905253740496
%N Number of n X n 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order
%C Diagonal of A240636
%e Some solutions for n=4
%e ..0..1..0..0....0..1..1..1....0..1..0..1....0..0..1..1....0..1..0..1
%e ..0..1..0..1....1..1..0..0....0..1..0..0....1..1..0..1....0..0..0..0
%e ..0..1..1..0....0..0..1..1....1..0..1..1....0..0..0..0....1..1..0..0
%e ..1..0..1..1....1..0..1..1....1..1..1..0....1..1..0..0....0..1..1..1
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 09 2014
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