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A304539 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4 or 6 king-move adjacent elements, with upper left element zero. 1
3, 7, 9, 19, 37, 65, 129, 275, 555, 1143, 2417, 5101, 10937, 23873, 52511, 116647, 261813, 592025, 1347981, 3088537, 7111583, 16443119, 38153839, 88783305, 207079559, 483922933, 1132625887, 2654229335, 6226282429, 14617442181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304544.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) -a(n-2) +2*a(n-3) -8*a(n-4) +2*a(n-5) -a(n-6) -a(n-7) -9*a(n-8) +3*a(n-9) +9*a(n-10) +8*a(n-11) +a(n-12) -3*a(n-13)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304544.

Sequence in context: A034926 A224849 A304128 * A306124 A096102 A316157

Adjacent sequences:  A304536 A304537 A304538 * A304540 A304541 A304542

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 14 2018

STATUS

approved

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Last modified June 13 06:38 EDT 2021. Contains 344981 sequences. (Running on oeis4.)