%I #6 Apr 21 2020 13:02:50
%S 1,8,24,96,278,706,1887,4795,11794,28951,70400,167177,395417,926397,
%T 2160731,4999028
%N Number of n X n 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
%C Diagonal of A281469.
%e Some solutions for n=4
%e ..0..0..1..1. .0..1..1..0. .0..1..1..0. .0..0..1..0. .0..0..1..1
%e ..1..0..1..0. .0..1..0..0. .0..0..1..0. .1..0..1..0. .1..0..1..0
%e ..1..0..1..1. .0..1..0..1. .1..0..1..0. .1..0..1..0. .1..0..1..0
%e ..1..0..0..1. .1..1..0..1. .1..0..1..1. .0..0..1..0. .0..0..1..1
%Y Cf. A281469.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 22 2017
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