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A305247 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4 or 8 king-move adjacent elements, with upper left element zero. 1
3, 7, 10, 17, 34, 65, 121, 244, 502, 1023, 2112, 4430, 9384, 20081, 43341, 94137, 205643, 451538, 995569, 2202392, 4885309, 10860185, 24185234, 53936572, 120423583, 269112504, 601825056, 1346656482, 3014688479, 6751281413 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305252.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-4) -4*a(n-5) -a(n-6) -10*a(n-7) -10*a(n-8) -3*a(n-9) +6*a(n-11) +2*a(n-12)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305252.

Sequence in context: A022120 A041191 A304216 * A316547 A041251 A042435

Adjacent sequences:  A305244 A305245 A305246 * A305248 A305249 A305250

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 28 2018

STATUS

approved

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Last modified October 23 16:20 EDT 2021. Contains 348215 sequences. (Running on oeis4.)