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%I #6 Apr 20 2020 19:53:36
%S 0,216,103296,240637408,2840332868960,190428267451649488,
%T 74703200829032822656704,174692108176538512510958268440
%N Number of n X n 0..4 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling four exactly once.
%C Diagonal of A269829.
%e Some solutions for n=3
%e ..2..3..2. .3..4..4. .3..2..0. .4..4..3. .0..2..1. .0..4..2. .3..2..0
%e ..1..4..3. .2..4..2. .3..0..0. .3..2..4. .3..3..0. .3..3..4. .1..0..1
%e ..1..2..3. .4..3..2. .4..2..3. .1..4..1. .0..3..3. .2..4..4. .0..1..2
%Y Cf. A269829.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 05 2016
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