%I #6 Aug 20 2020 11:38:13
%S 0,3,53,2229,240463,67479838,48809162176,90926518437773,
%T 436444614204907032,5400843845781866915026,172295115662202424268978762
%N Number of n X n 0..1 arrays with every element equal to 1, 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Diagonal of A300689.
%e Some solutions for n=5
%e ..0..0..0..0..1. .0..0..0..0..1. .0..0..0..0..1. .0..0..0..0..0
%e ..0..1..1..1..1. .0..1..0..1..1. .0..1..1..0..1. .0..1..1..0..1
%e ..1..0..0..0..1. .1..0..1..0..0. .0..0..1..1..0. .1..0..1..0..1
%e ..1..1..1..1..0. .0..1..0..1..0. .1..0..0..1..0. .0..1..0..1..0
%e ..0..0..0..0..0. .1..1..1..1..0. .1..1..0..0..0. .0..0..1..1..0
%Y Cf. A300689.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 11 2018
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