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A299881
Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
1
3, 4, 10, 28, 44, 222, 573, 1551, 5437, 15427, 46610, 147825, 440906, 1355665, 4185876, 12728958, 39141678, 120148173, 367673251, 1129038626, 3462538638, 10614970449, 32572123774, 99893671708, 306375998766, 939858679672
OFFSET
1,1
COMMENTS
Column 3 of A299886.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +3*a(n-2) +13*a(n-3) -27*a(n-4) -25*a(n-5) -51*a(n-6) +69*a(n-7) +57*a(n-8) +44*a(n-9) +75*a(n-10) +9*a(n-11) -109*a(n-12) -88*a(n-13) -49*a(n-14) -51*a(n-15) +19*a(n-16) +20*a(n-17) +2*a(n-18) for n>19
EXAMPLE
Some solutions for n=5
..0..0..0. .0..1..0. .0..0..0. .0..0..1. .0..1..1. .0..0..1. .0..0..1
..0..0..0. .0..1..0. .0..0..0. .0..0..0. .1..1..1. .0..0..1. .0..0..1
..1..1..1. .0..0..0. .0..0..1. .0..0..0. .1..1..1. .0..1..1. .1..1..1
..1..1..1. .0..0..0. .0..0..0. .0..1..0. .1..1..1. .0..0..1. .0..0..1
..1..1..0. .0..0..0. .1..0..1. .0..1..0. .1..1..1. .0..0..1. .0..0..1
CROSSREFS
Cf. A299886.
Sequence in context: A169790 A014009 A274220 * A218293 A374313 A288110
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 21 2018
STATUS
approved