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A209648 Number of nX6 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically 1
22, 484, 2354, 7128, 16830, 34012, 61754, 103664, 163878, 247060, 358402, 503624, 688974, 921228, 1207690, 1556192, 1975094, 2473284, 3060178, 3745720, 4540382, 5455164, 6501594, 7691728, 9038150, 10553972, 12252834, 14148904, 16256878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A209650

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 22*n^4 + (88/3)*n^3 - 22*n^2 - (22/3)*n

EXAMPLE

Some solutions for n=4

..0..1..0..1..1..0....0..1..0..1..1..0....1..1..1..0..1..0....1..0..1..1..1..0

..1..0..1..0..1..1....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..1..1

..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..0..1

..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..0..1

CROSSREFS

Sequence in context: A207664 A208005 A207567 * A207755 A207936 A208696

Adjacent sequences:  A209645 A209646 A209647 * A209649 A209650 A209651

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 11 2012

STATUS

approved

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Last modified July 28 12:23 EDT 2014. Contains 244997 sequences.