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A304349 Number of nX2 0..1 arrays with every element unequal to 0, 1, 3, 4 or 5 king-move adjacent elements, with upper left element zero. 8
2, 5, 9, 21, 57, 125, 289, 741, 1737, 4045, 9969, 23861, 56217, 135965, 326849, 776581, 1864297, 4479085, 10691729, 25606101, 61438777, 146972605, 351821409, 843331621, 2019112457, 4833683725, 11580336689, 27733236341, 66402706137 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A304355.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) -a(n-2) +8*a(n-3) -8*a(n-4)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304355.

Sequence in context: A155042 A001851 A303963 * A024822 A218966 A029726

Adjacent sequences:  A304346 A304347 A304348 * A304350 A304351 A304352

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 11 2018

STATUS

approved

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Last modified January 21 11:44 EST 2019. Contains 319354 sequences. (Running on oeis4.)