A182070 - OEIS

%I #12 Dec 18 2015 18:17:27

%S 1,2,35,8292,43324498,7006657352045

%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 horizontal, diagonal or antidiagonal neighbor

%e Some solutions for n=4

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

%e ..0.1......1.2......1.2......1.2......1.2......1.2......1.2......0.1

%e ..2.3.4....1.0.3....3.4.1....0.3.4....3.4.5....1.3.0....3.4.1....2.1.3

%e ..1.3.4.2..1.4.1.4..2.4.5.3..1.3.1.2..5.4.5.2..4.3.1.2..5.0.1.5..0.1.2.0

%K nonn

%O 1,2

%A _R. H. Hardin_ Apr 26 2012