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A305913 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 5 or 7 king-move adjacent elements, with upper left element zero. 1
3, 9, 13, 27, 62, 135, 312, 825, 2367, 6940, 21330, 67814, 216690, 699884, 2279373, 7427118, 24244543, 79292187, 259332414, 848386032, 2776599349, 9087224618, 29741257114, 97348224464, 318637326698, 1042951906150, 3413821643656 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305918.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +a(n-2) +7*a(n-3) -19*a(n-4) -21*a(n-5) +18*a(n-6) -23*a(n-7) +17*a(n-8) +55*a(n-9) +83*a(n-10) -23*a(n-11) -120*a(n-12) -20*a(n-13) +78*a(n-14) +9*a(n-15) -22*a(n-16) +2*a(n-18) for n>20

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305918.

Sequence in context: A014861 A018407 A304350 * A215443 A304664 A068885

Adjacent sequences:  A305910 A305911 A305912 * A305914 A305915 A305916

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 14 2018

STATUS

approved

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Last modified December 7 17:41 EST 2019. Contains 329847 sequences. (Running on oeis4.)