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A195272 Number of lower triangles of an n X n integer array with each element differing from all of its vertical and horizontal neighbors by 2 or less and triangles differing by a constant counted only once.

%I A195272 #9 Jul 22 2025 12:43:03
%S A195272 1,25,2125,626525,649112125,2375645170875,30812488814662125,
%T A195272 1419187229961716246975,232443697109891957009442125,
%U A195272 135513533218801266004475511024825
%N A195272 Number of lower triangles of an n X n integer array with each element differing from all of its vertical and horizontal neighbors by 2 or less and triangles differing by a constant counted only once.
%C A195272 Column 2 of A195278
%H A195272 R. H. Hardin, <a href="/A195272/b195272.txt">Table of n, a(n) for n = 1..11</a>
%e A195272 Some solutions for n=5
%e A195272 ...0...............0...............0...............0...............0
%e A195272 ..-2.-1...........-1..0...........-1..1...........-2..0............2..1
%e A195272 ...0..1..3........-3.-2..0........-3.-1..1........-1..0.-1.........0.-1..1
%e A195272 ...2..1..2..0.....-1.-3.-1.-2.....-3.-3.-1..0.....-2..0.-1..0.....-2.-1..1..2
%e A195272 ...4..3..4..2..3...0.-1.-3.-4.-3..-5.-4.-3.-1..0..-1.-1.-2..0..0..-4.-2.-1..0..1
%K A195272 nonn
%O A195272 1,2
%A A195272 _R. H. Hardin_ Sep 14 2011