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A235975
Number of (n+1)X(2+1) 0..2 arrays with the upper median equal to the lower median in every 2X2 subblock
1
181, 1473, 11239, 89555, 703565, 5579529, 44112111, 349456139, 2766556005, 21911565169, 173518250295, 1374222186243, 10883168081725, 86191072211609, 682600082348735, 5405952460295995, 42813179725209813, 339065137371681409
OFFSET
1,1
COMMENTS
Column 2 of A235981
LINKS
FORMULA
Empirical: a(n) = 11*a(n-1) -9*a(n-2) -173*a(n-3) +380*a(n-4) +324*a(n-5) -1056*a(n-6) +176*a(n-7) +256*a(n-8) -64*a(n-9)
EXAMPLE
Some solutions for n=4
..1..1..0....2..0..1....0..1..1....1..2..1....2..0..1....1..1..2....1..2..0
..1..1..2....0..0..0....2..1..1....1..1..1....1..1..1....1..1..0....2..2..2
..0..2..2....0..0..0....1..1..1....1..1..2....2..1..1....2..1..1....0..2..1
..1..1..2....1..0..1....0..1..0....1..1..0....1..1..1....1..1..1....2..2..2
..2..0..1....1..1..2....2..1..1....0..1..1....1..0..1....1..1..2....2..2..1
CROSSREFS
Sequence in context: A107255 A163442 A268520 * A137530 A069763 A264289
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 17 2014
STATUS
approved