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%I #5 Dec 18 2015 18:17:27
%S 1,3,34,5587,22019098,2777234353850
%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 element at a city block distance of two
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..1.2......1.2......1.2......0.1......1.2......1.2......1.2......1.2
%e ..3.2.4....3.4.0....3.4.5....2.2.3....1.3.4....1.3.0....3.3.1....3.3.1
%e ..5.5.3.3..5.1.0.4..0.6.3.4..4.4.5.1..0.3.2.0..0.4.4.1..4.4.5.6..2.0.4.2
%K nonn
%O 1,2
%A _R. H. Hardin_ Apr 27 2012
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