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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
1
1, 25, 2125, 626525, 649112125, 2375645170875, 30812488814662125, 1419187229961716246975, 232443697109891957009442125, 135513533218801266004475511024825
OFFSET
1,2
COMMENTS
Column 2 of A195278
LINKS
EXAMPLE
Some solutions for n=5
...0...............0...............0...............0...............0
..-2.-1...........-1..0...........-1..1...........-2..0............2..1
...0..1..3........-3.-2..0........-3.-1..1........-1..0.-1.........0.-1..1
...2..1..2..0.....-1.-3.-1.-2.....-3.-3.-1..0.....-2..0.-1..0.....-2.-1..1..2
...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
CROSSREFS
Sequence in context: A279276 A197408 A197430 * A266130 A363192 A222276
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 14 2011
STATUS
approved