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A305477 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 6 or 8 king-move adjacent elements, with upper left element zero. 1
3, 7, 10, 21, 40, 70, 125, 231, 419, 752, 1365, 2482, 4488, 8121, 14729, 26689, 48322, 87545, 158636, 287360, 520537, 943067, 1708503, 3095024, 5606953, 10157742, 18401740, 33336465, 60392685, 109407857, 198203346, 359065917, 650486008 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305482.

LINKS

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

Simon Plouffe, Conjectures of the OEIS, as of June 20, 2018.

FORMULA

Empirical: a(n) = a(n-1) +3*a(n-3) -2*a(n-6) for n>9.

Empirical: -x*(-2*x^8-2*x^6-2*x^4+2*x^3+3*x^2+4*x+3)/(-2*x^6+3*x^3+x-1). - Simon Plouffe, Jun 20 2018

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305482.

Sequence in context: A255180 A053159 A279912 * A316306 A317261 A024464

Adjacent sequences:  A305474 A305475 A305476 * A305478 A305479 A305480

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 02 2018

STATUS

approved

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Last modified April 14 22:47 EDT 2021. Contains 342971 sequences. (Running on oeis4.)