%I #6 Jun 22 2022 11:25:17
%S 0,0,67,10112,743866,20556897,303369413,2935224783,20968226394
%N Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-5.
%C Column 4 of A211963.
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..1.2......1.1......1.2......1.2......1.1......1.2......1.2......1.1
%e ..0.2.3....2.3.4....0.3.4....3.4.3....2.3.4....3.2.3....3.3.3....0.0.2
%e ..0.4.3.5..1.5.5.1..5.2.0.3..3.5.0.2..2.0.2.5..4.2.5.4..0.4.2.5..3.4.5.0
%Y Cf. A211963.
%K nonn
%O 1,3
%A _R. H. Hardin_, Apr 26 2012
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