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A201379
Number of nX3 0..1 arrays with rows and columns lexicographically nondecreasing and the instance counts of every value within one of each other
1
2, 4, 19, 27, 115, 122, 467, 433, 1461, 1208, 3797, 2931, 8642, 6292, 17780, 12430, 33822, 22825, 60401, 39688, 102439, 65739, 166387, 104780, 260549, 161323, 395367, 241382, 583802, 351915, 841664, 501871, 1188050, 701410, 1645719, 963241
OFFSET
1,1
COMMENTS
Column 3 of A201384
LINKS
FORMULA
Empirical: a(n) = 4*a(n-2) -3*a(n-4) -8*a(n-6) +14*a(n-8) -14*a(n-12) +8*a(n-14) +3*a(n-16) -4*a(n-18) +a(n-20)
EXAMPLE
Some solutions for n=10
..0..0..1....0..0..0....0..0..1....0..0..1....0..0..0....0..0..1....0..0..0
..0..1..0....0..0..0....0..1..0....0..1..0....0..0..1....0..0..1....0..0..1
..0..1..0....0..0..1....0..1..0....0..1..0....0..0..1....0..0..1....0..0..1
..0..1..0....0..1..1....0..1..1....0..1..0....0..1..0....0..0..1....0..0..1
..0..1..1....0..1..1....0..1..1....1..0..0....0..1..0....0..1..1....0..0..1
..1..0..0....0..1..1....1..0..0....1..0..0....0..1..0....1..0..0....0..1..1
..1..0..1....0..1..1....1..0..0....1..0..1....1..0..1....1..0..1....1..0..1
..1..1..0....1..0..0....1..0..1....1..1..0....1..1..0....1..0..1....1..1..0
..1..1..0....1..1..0....1..1..0....1..1..0....1..1..1....1..0..1....1..1..0
..1..1..0....1..1..1....1..1..0....1..1..1....1..1..1....1..1..0....1..1..1
CROSSREFS
Sequence in context: A184308 A268338 A171735 * A056727 A154140 A131578
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 30 2011
STATUS
approved