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A305335 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 5 or 8 king-move adjacent elements, with upper left element zero. 1
4, 5, 12, 26, 62, 166, 431, 1091, 2812, 7268, 18741, 48294, 124560, 321313, 828693, 2137285, 5512541, 14218105, 36671374, 94583059, 243949927, 629198761, 1622836684, 4185639740, 10795653340, 27844280385, 71816305058, 185229485865 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305340.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +3*a(n-2) +3*a(n-3) +2*a(n-4) -3*a(n-5) -8*a(n-6) -4*a(n-7) for n>8

EXAMPLE

Some solutions for n=5

..0..0..0. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..0..0

..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0

..0..1..0. .1..0..0. .1..0..0. .0..0..1. .0..0..0. .0..0..0. .1..0..0

..0..0..0. .0..0..0. .0..0..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0

..0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..1..0

CROSSREFS

Cf. A305340.

Sequence in context: A309479 A352720 A308775 * A123102 A274077 A028272

Adjacent sequences:  A305332 A305333 A305334 * A305336 A305337 A305338

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 30 2018

STATUS

approved

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Last modified May 26 13:59 EDT 2022. Contains 354092 sequences. (Running on oeis4.)