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%I #5 Dec 18 2015 18:17:44
%S 1,3,33,1620,136080,17962560,3751608960,1233597237120,641473938397440,
%T 526921921428975360
%N Number of lower triangles of an n X n 0..4 array with new values introduced in row major order 0..4 and no two horizontal or vertical neighbors of any element equal
%C Column 4 of A194893
%e Some solutions for 4X4
%e ..0........0........0........0........0........0........0........0
%e ..1.2......0.1......1.2......1.1......0.1......1.2......0.1......1.1
%e ..3.0.1....2.3.4....1.3.0....2.3.4....2.1.3....1.2.3....2.1.0....2.3.3
%e ..4.0.3.2..2.0.1.1..0.4.2.1..2.0.1.1..2.0.4.4..4.0.1.4..2.3.0.1..2.0.4.2
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 04 2011
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