A206266 Number of (n+1) X 8 0..1 arrays with the number of rightwards and downwards edge increases in each 2 X 2 subblock equal to the number in all its horizontal and vertical neighbors.

154, 174, 503, 1296, 3011, 6444, 12878, 24319, 43766, 75591, 125978, 203499, 319778, 490323, 735479, 1081584, 1562283, 2220084, 3108113, 4292154, 5852933, 7888734, 10518308, 13884165, 18156212, 23535829, 30260348, 38608029, 48903500, 61523757

Offset

1,1

Comments

Column 7 of A206267.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) - 27*a(n-2) + 48*a(n-3) - 42*a(n-4) + 42*a(n-6) - 48*a(n-7) + 27*a(n-8) - 8*a(n-9) + a(n-10) for n>11.

Empirical g.f.: x*(154 - 1058*x + 3269*x^2 - 5422*x^3 + 4340*x^4 + 512*x^5 - 4927*x^6 + 5271*x^7 - 2862*x^8 + 826*x^9 - 101*x^10) / ((1 - x)^9*(1 + x)). - Colin Barker, Jun 15 2018

Example

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

Crossrefs

Cf. A206267.

Sequence in context: A269664 A281857 A278708 * A049515 A049519 A214475

Adjacent sequences: A206263 A206264 A206265 * A206267 A206268 A206269

Keyword

nonn

Author

R. H. Hardin, Feb 05 2012

Status

approved