A209648 Number of n X 6 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.

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

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.

Conjectures from Colin Barker, Jul 12 2018: (Start)

G.f.: 22*x*(1 + 17*x + 7*x^2 - x^3) / (1 - x)^5.

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.

(End)

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

Cf. A209650.

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