A281468 Number of nX7 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

64, 361, 145, 260, 472, 924, 1887, 3681, 7126, 14363, 29371, 59830, 122230, 250638, 513616, 1053242, 2163243, 4442634, 9122210, 18740008, 38502723, 79097291, 162508103, 333905314, 686048845, 1409580474, 2896272475, 5950951790

Offset

1,1

Comments

Column 7 of A281469.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-3) -4*a(n-4) -4*a(n-5) +a(n-7) +2*a(n-8) -a(n-9) +5*a(n-10) -3*a(n-12) for n>19

Example

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

Crossrefs

Cf. A281469.

Sequence in context: A299681 A300313 A137739 * A302622 A302414 A303181

Adjacent sequences: A281465 A281466 A281467 * A281469 A281470 A281471

Keyword

nonn

Author

R. H. Hardin, Jan 22 2017

Status

approved