A297425 - OEIS

%I #6 May 03 2020 15:30:00

%S 1,2,14,42,535,11345,431723,28588498,3362921639,861591734557,

%T 416496898515488,327244273979649876,483572529979247043390

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

%C Diagonal of A297431.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A297431.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 30 2017