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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
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: A352720 A369697 A308775 * A123102 A274077 A028272
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 30 2018
STATUS
approved

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Last modified July 23 19:43 EDT 2024. Contains 374553 sequences. (Running on oeis4.)