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A195950
Number of lower triangles of an n X n 0..3 array with no element greater than the number its nonzero horizontal and vertical neighbors
1
1, 5, 162, 17424, 6756437, 9790899054, 53438526965463, 1095434478598715742, 84189100478450762470628, 24264818647445156524051251366, 26234269948355443957604222160170467
OFFSET
1,2
LINKS
EXAMPLE
Some solutions for n=4
..1........1........1........0........1........1........0........0
..2.1......2.0......3.2......0.1......1.1......3.2......2.2......1.2
..1.2.0....3.3.2....1.3.0....2.1.2....3.2.2....2.1.1....1.1.1....1.1.1
..0.2.1.1..2.1.1.1..2.1.1.0..2.2.1.1..1.3.2.0..1.2.3.1..2.2.2.1..0.2.1.0
CROSSREFS
Sequence in context: A117068 A185832 A301667 * A195951 A128068 A197095
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 25 2011
STATUS
approved