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A184131
Number of nX3 0..2 arrays with rows and columns in nondecreasing order
1
10, 112, 1169, 10020, 70243, 414848, 2126064, 9681099, 39886396, 150795172, 528970102, 1737120632, 5379657012, 15806662276, 44290055378, 118862126126, 306675218582, 763173754851, 1837012424988, 4287769072145, 9726214524190
OFFSET
1,1
COMMENTS
Column 3 of A184137
LINKS
FORMULA
Empirical: a(n)=27*a(n-1)-351*a(n-2)+2925*a(n-3)-17550*a(n-4)+80730*a(n-5)-296010*a(n-6)+888030*a(n-7)-2220075*a(n-8)+4686825*a(n-9)-8436285*a(n-10)+13037895*a(n-11)-17383860*a(n-12)+20058300*a(n-13)-20058300*a(n-14)+17383860*a(n-15)-13037895*a(n-16)+8436285*a(n-17)-4686825*a(n-18)+2220075*a(n-19)-888030*a(n-20)+296010*a(n-21)-80730*a(n-22)+17550*a(n-23)-2925*a(n-24)+351*a(n-25)-27*a(n-26)+a(n-27) (=polynomial of degree 26)
EXAMPLE
Some solutions for 5X3
..0..1..2....0..0..1....0..0..1....0..0..2....0..0..2....0..1..1....0..1..1
..1..0..0....0..0..2....0..2..2....0..1..2....0..1..0....0..1..2....0..1..2
..1..1..2....1..2..1....1..1..0....1..1..1....1..1..0....0..2..2....2..0..0
..1..1..2....1..2..1....1..2..0....1..2..1....1..1..2....0..2..2....2..0..2
..1..1..2....1..2..1....2..2..0....1..2..2....2..2..2....2..0..1....2..2..1
CROSSREFS
Sequence in context: A344398 A046164 A322724 * A239651 A014484 A110040
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 09 2011
STATUS
approved