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%I #6 Dec 18 2015 18:17:46
%S 1,5,162,19913,10408097,23663085157,233759541159316,
%T 10022979661615617883,1865159356600749113021208,
%U 1506395624918723916292924776440,5280426678910236576404521138602764328
%N Number of lower triangles of an n X n 0..4 array with no element greater than the number its nonzero horizontal and vertical neighbors
%H R. H. Hardin, <a href="/A195951/b195951.txt">Table of n, a(n) for n = 1..13</a>
%e Some solutions for n=4
%e ..1........1........1........1........1........0........1........1
%e ..1.0......1.0......3.1......1.2......2.2......2.2......2.2......1.1
%e ..2.3.1....1.3.1....2.4.1....2.2.2....1.3.1....2.3.2....1.3.0....3.3.0
%e ..2.3.3.1..2.1.1.1..2.1.3.1..2.3.2.1..2.1.2.0..1.1.2.0..0.2.1.1..2.3.1.1
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 25 2011
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