A208836 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically.

10, 100, 282, 855, 3010, 11242, 44275, 179032, 737550, 3070375, 12868830, 54154926, 228475507, 965411356, 4083220786, 17280246775, 73157026602, 309784875682, 1311973439667, 5556832891632, 23537091290566, 99699402777415

Offset

1,1

Comments

Column 4 of A208840.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) - 8*a(n-2) - 27*a(n-3) + 45*a(n-4) + 24*a(n-5) - 51*a(n-6) - 3*a(n-7) + 16*a(n-8) - a(n-9) - a(n-10) for n>11.

Empirical g.f.: x*(10 + 30*x - 338*x^2 - 49*x^3 + 1531*x^4 - 114*x^5 - 1834*x^6 + 200*x^7 + 612*x^8 - 63*x^9 - 41*x^10) / ((1 - x)*(1 + x)*(1 - 3*x + x^2)*(1 + x - x^2)*(1 - x - x^2)*(1 - 4*x - x^2)). - Colin Barker, Mar 07 2018

Example

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

Crossrefs

Cf. A208840.

Sequence in context: A207028 A207173 A207456 * A208684 A207348 A207770

Adjacent sequences: A208833 A208834 A208835 * A208837 A208838 A208839

Keyword

nonn

Author

R. H. Hardin, Mar 01 2012

Status

approved