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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
OFFSET
1,1
COMMENTS
Column 7 of A281469.
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 22 2017
STATUS
approved