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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. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified July 23 10:56 EDT 2021. Contains 346259 sequences. (Running on oeis4.)