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A195213 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 1 or less and triangles differing by a constant counted only once 2
1, 7, 91, 2277, 111031, 10654607, 2021888119, 761408842173, 570411420721871, 851650667866314005, 2537743716708476573853, 15108768742290768272235707, 179885152873727967922701202921, 4286156683596201247493358770260469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 1 of A195220

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..16

EXAMPLE

Some solutions for n=5

...0...............0...............0...............0...............0

...1..0...........-1.-1...........-1..0...........-1..0............1..1

...0..0..1........-2.-2.-1........-1..0..1.........0..0.-1.........0..1..0

...0..1..1..1.....-1.-1.-1.-2......0..0..0..1......1..0.-1.-2......0..1..1..0

...1..0..1..0..0..-1.-1.-2.-1.-2...0..0..1..1..2...1..0.-1.-2.-1...0..0..1..1..0

CROSSREFS

Sequence in context: A177784 A326266 A124557 * A317370 A282041 A027955

Adjacent sequences:  A195210 A195211 A195212 * A195214 A195215 A195216

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 13 2011

STATUS

approved

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Last modified December 10 15:09 EST 2019. Contains 329896 sequences. (Running on oeis4.)