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Number of n X n 0..1 arrays with every element unequal to 1, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero.
0

%I #6 Oct 28 2020 19:06:16

%S 0,7,42,496,11282,435964,30361694,3805684538,844100991906

%N Number of n X n 0..1 arrays with every element unequal to 1, 2, 3, 5 or 7 king-move adjacent elements, with upper left element zero.

%C Diagonal of A304959.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A304959.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 22 2018