A208706 Number of n X 5 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

16, 356, 8128, 185344, 4226368, 96373248, 2197585152, 50111214592, 1142678737920, 26056337063936, 594158864306176, 13548518165364736, 308944889161203712, 7044825373067575296, 160642128347753938944

Offset

1,1

Comments

Column 5 of A208709.

Links

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

Formula

Empirical: a(n) = 24*a(n-1) - 28*a(n-2) + 16*a(n-3) for n>4.

Empirical g.f.: 4*x*(4 - 7*x + 8*x^2 - 4*x^3) / (1 - 24*x + 28*x^2 - 16*x^3). - Colin Barker, Jul 06 2018

Example

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

Crossrefs

Cf. A208709.

Sequence in context: A053103 A223032 A171680 * A278622 A155122 A094101

Adjacent sequences: A208703 A208704 A208705 * A208707 A208708 A208709

Keyword

nonn

Author

R. H. Hardin, Mar 01 2012

Status

approved