A295914 Number of n X 4 0..1 arrays with each 1 adjacent to 0 or 3 king-move neighboring 1s.

8, 28, 115, 467, 1880, 7604, 30721, 124117, 501512, 2026304, 8187195, 33079959, 133657824, 540037688, 2181994609, 8816237625, 35621557528, 143927081684, 581530015059, 2349642293451, 9493609553944, 38358444014860, 154985331853649

Offset

1,1

Links

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

Formula

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

Empirical g.f.: x*(8 + 12*x + 3*x^2 - 7*x^3 - 3*x^4 + x^5) / ((1 + x)*(1 - 3*x - 4*x^2 - 2*x^3 + 5*x^4 - x^5)). - Colin Barker, Feb 22 2019

Example

Some solutions for n=7:
..1..0..0..0. .0..1..0..0. .0..0..0..1. .0..0..0..1. .0..0..0..1
..0..0..1..0. .0..0..0..0. .1..0..0..0. .1..0..0..0. .1..1..0..0
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0. .1..1..0..0
..1..1..0..0. .0..0..0..0. .0..1..0..1. .0..0..0..0. .0..0..0..1
..1..1..0..0. .0..0..1..0. .0..0..0..0. .0..0..0..0. .1..0..0..0
..0..0..0..1. .1..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..1. .0..1..0..0

Crossrefs

Column 4 of A295918.

Sequence in context: A317607 A306545 A358285 * A054857 A241893 A200188

Adjacent sequences: A295911 A295912 A295913 * A295915 A295916 A295917

Keyword

nonn

Author

R. H. Hardin, Nov 29 2017

Status

approved