A259955 Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001001.

34, 67, 155, 353, 808, 1884, 4340, 9925, 22799, 52515, 120848, 277830, 638728, 1468871, 3378335, 7769445, 17866796, 41087200, 94488464, 217296769, 499716771, 1149192279, 2642787772, 6077609506, 13976655996, 32142038875, 73916854091

Offset

1,1

Links

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

Formula

Empirical: a(n) = a(n-1) + 3*a(n-3) + 5*a(n-4) + 6*a(n-5) + 6*a(n-6) + 2*a(n-7) for n>8.

Empirical g.f.: x*(34 + 33*x + 88*x^2 + 96*x^3 + 84*x^4 + 72*x^5 + 16*x^6 - 4*x^7) / (1 - x - 3*x^3 - 5*x^4 - 6*x^5 - 6*x^6 - 2*x^7). - Colin Barker, Dec 27 2018

Example

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

Crossrefs

Column 1 of A259962.

Sequence in context: A043984 A259962 A259894 * A259887 A028381 A277113

Adjacent sequences: A259952 A259953 A259954 * A259956 A259957 A259958

Keyword

nonn

Author

R. H. Hardin, Jul 10 2015

Status

approved