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A304304 Number of nX2 0..1 arrays with every element unequal to 0, 1, 2, 3 or 5 king-move adjacent elements, with upper left element zero. 8
2, 8, 23, 65, 192, 569, 1709, 5162, 15663, 47669, 145352, 443789, 1356105, 4146218, 12681419, 38795969, 118706016, 363247697, 1111633973, 3402041162, 10411891095, 31866011357, 97528388600, 298495524005, 913580540913, 2796129772298 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A304310.

LINKS

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

FORMULA

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

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304310.

Sequence in context: A294959 A290926 A018042 * A072842 A303861 A138387

Adjacent sequences:  A304301 A304302 A304303 * A304305 A304306 A304307

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 10 2018

STATUS

approved

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Last modified April 19 20:04 EDT 2019. Contains 322291 sequences. (Running on oeis4.)