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%I #4 Dec 18 2015 18:18:10
%S 0,3,28,338,2440,11859,43943,134273,355568,843290,1832469,3708583,
%T 7075643,12844948,22348290,37479704,60870173,96100013,147953978,
%U 222724440,328568314,475923713
%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, and containing the value n(n+1)/2-3
%C Column 2 of A212036
%F Empirical: a(n) = (1/128)*n^8 + (1/32)*n^7 - (53/192)*n^6 - (1/16)*n^5 + (545/128)*n^4 - (1129/96)*n^3 + (913/96)*n^2 + (175/24)*n - 10 for n>1
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..1.2......0.1......1.2......1.2......1.2......1.2......0.1......1.2
%e ..3.4.5....2.3.4....3.4.4....3.3.0....1.3.4....1.3.4....2.3.4....3.4.5
%e ..6.0.7.6..5.6.2.7..5.6.6.7..4.5.6.7..5.6.7.3..5.6.7.2..5.6.6.7..0.6.7.0
%K nonn
%O 1,2
%A _R. H. Hardin_ Apr 27 2012
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