%I #6 Apr 25 2023 13:13:59
%S 1,21,402,7154,118863,2076117,37066859,666849212,12062165754,
%T 218944306666,3980414427158,72424065007263,1318344476372801,
%U 24003514023779867,437093903871650760,7959828410582705257
%N Number of n X 7 0..1 arrays with no element equal to exactly one horizontal or vertical neighbor, with new values 0..1 introduced in row major order.
%C Column 7 of A240656.
%H R. H. Hardin, <a href="/A240655/b240655.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..0..0..0..0..0..1....0..1..1..1..1..1..1....0..0..0..1..0..0..0
%e ..0..0..1..0..0..0..0....1..1..0..1..0..0..1....0..0..0..0..0..0..0
%e ..0..0..0..1..0..0..0....1..1..1..1..0..0..1....0..1..0..1..0..0..0
%e ..0..0..0..0..0..0..0....0..1..1..1..1..1..1....0..0..0..0..0..0..1
%Y Cf. A240656.
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 09 2014
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