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%I #6 Apr 20 2020 19:40:18
%S 1,1,6,9,70,473,10708,348557,4845667,64933909,9012724549,927373554115,
%T 90953901974416,39400271219843985,17050653134989917553,
%U 3479394369545306732310
%N Number of n X n integer arrays with each element equal to the number of horizontal and antidiagonal neighbors equal to itself.
%C Diagonal of A266012.
%e Some solutions for n=4
%e ..0..2..2..1....0..2..2..1....0..1..2..2....0..2..2..0....0..2..2..0
%e ..2..2..1..0....2..2..1..0....1..2..2..0....2..2..1..1....2..2..1..0
%e ..0..2..2..0....0..2..2..1....0..1..2..2....0..2..2..1....0..1..2..2
%e ..2..2..1..1....2..2..1..0....1..2..2..0....2..2..1..0....0..2..2..0
%Y Cf. A266012.
%K nonn
%O 1,3
%A _R. H. Hardin_, Dec 20 2015