A269069 - OEIS

%I #7 Apr 19 2020 23:46:51

%S 2,11,123,3288,165607,18220241,4064720816,1833956006577,

%T 1778703508587227,3374673365461249568,14101540722268888633757,

%U 114651904507399541002097761,2060026489521744559823250922304,72580676762280474254836112626897875

%N Number of n X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

%C Diagonal of A269075.

%H R. H. Hardin, <a href="/A269069/b269069.txt">Table of n, a(n) for n = 1..23</a>

%e Some solutions for n=4

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

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

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

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

%Y Cf. A269075.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 19 2016