A268743 - OEIS

%I #7 Apr 19 2020 23:42:05

%S 2,11,143,4110,255651,34732937,10319681062,6744840113811,

%T 9736268648482947,31152408949342676906,221573405414594347811555,

%U 3511390061199964238627005057,124222798189336185449669887550302

%N Number of n X n binary arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.

%C Diagonal of A268750.

%H R. H. Hardin, <a href="/A268743/b268743.txt">Table of n, a(n) for n = 1..26</a>

%e Some solutions for n=4

%e ..0..0..1..0. .0..1..1..0. .1..0..0..0. .0..0..0..1. .1..0..0..1

%e ..1..0..0..1. .0..0..0..0. .0..0..1..0. .0..1..0..0. .0..0..0..0

%e ..0..0..0..0. .0..1..0..1. .0..0..0..1. .0..1..0..1. .0..0..1..0

%e ..0..0..0..0. .0..0..0..0. .0..1..0..1. .1..0..0..0. .1..1..0..0

%Y Cf. A268750.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 12 2016