A297500 - OEIS

%I #6 May 03 2020 15:31:30

%S 1,10,110,2281,270845,66289769,28914051279,44145856928170,

%T 190314910908111935,1690602288933775004206,41411616264665765678770302

%N Number of n X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 2 neighboring 1's.

%C Diagonal of A297506.

%e Some solutions for n=4

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

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

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

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

%Y Cf. A297506.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 31 2017