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%I #6 Apr 20 2020 19:55:45
%S 0,1344,45440640,38799000374400,1043364062813432764992,
%T 953623090124975369688224358912,
%U 30710864722727618437291310619830386096704
%N Number of n X n 0..7 arrays with some element plus some horizontally or vertically adjacent neighbor totalling seven exactly once.
%C Diagonal of A270118.
%e Some solutions for n=2
%e ..5..2. .0..2. .0..0. .7..3. .5..1. .5..2. .4..5. .2..1. .7..5. .0..6
%e ..5..1. .6..5. .7..5. .4..3. .2..7. .3..1. .0..2. .5..0. .0..3. .7..7
%Y Cf. A270118.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 11 2016