A207065 Number of n X 5 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically.

14, 196, 896, 2688, 6398, 13132, 24304, 41664, 67326, 103796, 154000, 221312, 309582, 423164, 566944, 746368, 967470, 1236900, 1561952, 1950592, 2411486, 2954028, 3588368, 4325440, 5176990, 6155604, 7274736, 8548736, 9992878

Offset

1,1

Comments

Column 5 of A207068.

Links

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

Formula

Empirical: a(n) = (7/30)*n^5 + 7*n^4 + (21/2)*n^3 - (56/15)*n.

Conjectures from Colin Barker, Jun 18 2018: (Start)

G.f.: 14*x*(1 + 8*x - 5*x^2 - 2*x^3) / (1 - x)^6.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.

(End)

Example

Some solutions for n=4:
..0..1..1..1..0....0..0..0..0..0....1..1..0..0..0....1..0..1..1..0
..0..1..1..0..1....1..1..0..0..0....0..1..1..1..1....1..1..0..0..0
..0..0..0..0..0....1..1..0..0..0....0..1..1..0..1....0..0..0..0..0
..0..0..0..0..0....1..0..0..0..0....0..1..1..0..0....0..0..0..0..0

Crossrefs

Cf. A207068.

Sequence in context: A208695 A207245 A208166 * A207120 A207963 A207502

Adjacent sequences: A207062 A207063 A207064 * A207066 A207067 A207068

Keyword

nonn

Author

R. H. Hardin, Feb 14 2012

Status

approved