A281405 Number of 6 X n 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 676, 3838, 7064, 13446, 23216, 37462, 57468, 87252, 135112, 211998, 333400, 526832, 834536, 1322878, 2100904, 3340468, 5310496, 8440806, 13411668, 21294588, 33787028, 53571622, 84875628, 134369192, 212570368, 336041114, 530858836

Offset

1,2

Comments

Row 6 of A281400.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -6*a(n-2) +6*a(n-3) -7*a(n-4) +6*a(n-5) -a(n-6) -4*a(n-7) +5*a(n-8) -4*a(n-9) +4*a(n-10) -2*a(n-11) -a(n-12) +2*a(n-13) -a(n-14) for n>25.

Example

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

Crossrefs

Cf. A281400.

Sequence in context: A253330 A255076 A253323 * A204036 A235410 A239608

Adjacent sequences: A281402 A281403 A281404 * A281406 A281407 A281408

Keyword

nonn

Author

R. H. Hardin, Jan 21 2017

Status

approved