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A297980 Number of n X 2 0..1 arrays with every element equal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero. 2
1, 5, 6, 17, 24, 53, 94, 173, 340, 601, 1178, 2137, 4056, 7565, 14086, 26533, 49276, 92641, 172722, 323409, 604896, 1130389, 2116062, 3954141, 7399172, 13833769, 25873674, 48391369, 90490216, 169253917, 316506038, 591959445, 1107045516 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A297986.

LINKS

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

FORMULA

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

Empirical g.f.: x*(1 + 5*x + 3*x^2 - 2*x^4) / (1 - 3*x^2 - 2*x^3 + 2*x^4). - Colin Barker, Mar 22 2018

EXAMPLE

Some solutions for n=7:

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

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

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

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

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

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

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

CROSSREFS

Cf. A297986.

Sequence in context: A041997 A041773 A041054 * A120034 A094425 A078981

Adjacent sequences:  A297977 A297978 A297979 * A297981 A297982 A297983

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 10 2018

STATUS

approved

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Last modified September 21 21:32 EDT 2021. Contains 347605 sequences. (Running on oeis4.)