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A304297
Number of nX3 0..1 arrays with every element unequal to 1, 2, 5 or 8 king-move adjacent elements, with upper left element zero.
1
1, 2, 3, 5, 6, 14, 22, 33, 57, 97, 159, 255, 432, 724, 1171, 1951, 3254, 5363, 8858, 14694, 24381, 40260, 66642, 110538, 182870, 302621, 501272, 830095, 1374018, 2274695, 3767129, 6236893, 10324974, 17096385, 28307135, 46865638, 77594124, 128475252
OFFSET
1,2
COMMENTS
Column 3 of A304302.
LINKS
FORMULA
Empirical: a(n) = a(n-2) +3*a(n-3) +2*a(n-4) -4*a(n-6) -2*a(n-7) -a(n-8) -2*a(n-9)
EXAMPLE
All solutions for n=5
..0..0..0. .0..1..0. .0..0..0. .0..1..0. .0..1..0. .0..0..0
..0..1..0. .0..0..0. .1..0..1. .0..0..0. .0..0..0. .0..1..0
..0..0..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..1..0. .1..0..1. .0..1..0
..0..1..0. .0..1..0. .0..1..0. .0..0..0. .0..0..0. .0..0..0
CROSSREFS
Cf. A304302.
Sequence in context: A253647 A131825 A289124 * A249752 A222313 A355483
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 10 2018
STATUS
approved