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%I #6 Jun 26 2020 13:27:00
%S 0,1,2,28,1146,78195,17675111,9829599051,14061129641181,
%T 51771244646074395
%N Number of n X n 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Diagonal of A300465.
%e Some solutions for n=5
%e ..0..0..1..1..0. .0..0..0..1..1. .0..0..0..0..1. .0..0..1..1..1
%e ..0..1..1..0..0. .0..0..1..0..1. .0..1..0..1..1. .0..0..1..1..0
%e ..0..0..0..1..1. .1..1..0..0..1. .1..1..0..1..0. .0..0..1..0..0
%e ..1..1..0..1..0. .1..1..0..1..0. .0..0..1..0..0. .1..1..0..1..1
%e ..1..0..0..0..0. .1..1..1..0..0. .0..1..1..0..0. .1..0..0..1..1
%Y Cf. A300465.
%K nonn
%O 1,3
%A _R. H. Hardin_, Mar 06 2018
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