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%I #5 Dec 18 2015 18:17:45
%S 1,49,11319,12608631,68604760497,1833160598134397,
%T 241338657495589799523,156865927758847103008175635,
%U 504091149328239931994947830412175
%N Number of lower triangles of an n X n integer array with each element differing from all of its vertical and horizontal neighbors by 3 or less and triangles differing by a constant counted only once
%C Column 3 of A195278
%e Some solutions for n=5
%e ...0...............0...............0...............0...............0
%e ...3..4...........-2..0............2..4............1..2...........-3.-1
%e ...2..5..3........-3..0..3.........3..6..5.........0.-1.-1........-5.-2..1
%e ...0..2..2..2......0..0..0.-1......6..3..6..6......0..2..1..3.....-2..1..3..5
%e ...0..2..5..2..4..-3.-2.-3.-2.-1...6..5..6..8..9..-1..2..1..0.-3..-4.-2..0..2..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 14 2011