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A304770 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3 or 7 king-move adjacent elements, with upper left element zero. 1
4, 21, 27, 67, 139, 303, 685, 1511, 3316, 7349, 16265, 35899, 79332, 175408, 387618, 856555, 1893162, 4184055, 9246710, 20435743, 45164387, 99815208, 220596189, 487529334, 1077464178, 2381248108, 5262677458, 11630780579, 25704601383 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304775.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +2*a(n-4) -a(n-5) for n>8

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304775.

Sequence in context: A041821 A042429 A276400 * A316513 A273208 A273270

Adjacent sequences:  A304767 A304768 A304769 * A304771 A304772 A304773

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 18 2018

STATUS

approved

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Last modified October 3 18:24 EDT 2022. Contains 357237 sequences. (Running on oeis4.)