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%I #6 Dec 18 2015 18:17:45
%S 4,22,246,5428,237818,20729610,3601738548,1249159521262,
%T 865793424024974,1200356073563114252,3331551471246807302142,
%U 18523112376180844925948966,206425939461681776649215679048,4613382950875473008207859661034814
%N Number of lower triangles of an n X n 0..3 array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by one or less
%C Column 3 of A195232
%H R. H. Hardin, <a href="/A195227/b195227.txt">Table of n, a(n) for n = 1..18</a>
%e Some solutions for n=4
%e ..3........2........0........2........1........2........1........1
%e ..3.2......3.2......1.1......1.2......1.0......2.3......1.0......0.1
%e ..2.2.2....3.2.1....1.2.1....1.1.2....1.0.1....3.3.3....0.0.1....1.0.0
%e ..3.2.3.3..2.2.2.1..2.2.2.1..1.2.1.1..1.0.1.2..3.3.2.3..1.0.1.0..1.0.0.1
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 13 2011
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