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A297067 Number of n X 2 0..1 arrays with no 1 adjacent to 1 king-move neighboring 1. 1
3, 10, 32, 103, 350, 1201, 4143, 14353, 49844, 173276, 602727, 2097232, 7298725, 25403085, 88419267, 307764514, 1071262948, 3728865871, 12979534274, 45179596085, 157262816291, 547406567737, 1905434794508, 6632515135472 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) - a(n-2) - a(n-3) - 4*a(n-4) - 8*a(n-5).

Empirical g.f.: x*(3 - 2*x - 5*x^2 - 12*x^3 - 8*x^4) / (1 - 4*x + x^2 + x^3 + 4*x^4 + 8*x^5). - Colin Barker, Feb 25 2019

EXAMPLE

Some solutions for n=7:

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

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

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

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

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

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

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

CROSSREFS

Column 2 of A297073.

Sequence in context: A292398 A273351 A033505 * A063782 A071718 A261058

Adjacent sequences:  A297064 A297065 A297066 * A297068 A297069 A297070

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 24 2017

STATUS

approved

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Last modified October 16 09:29 EDT 2019. Contains 328056 sequences. (Running on oeis4.)