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Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 4, 5 or 6 king-move adjacent elements, with upper left element zero.
0

%I #4 Jun 07 2018 08:57:31

%S 1,4,29,334,8734,385282,42274045,12972861669,10445509134407

%N Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 4, 5 or 6 king-move adjacent elements, with upper left element zero.

%C Diagonal of A305642.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A305642.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jun 07 2018