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A304843 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero. 1
4, 12, 25, 51, 165, 419, 1009, 2697, 7091, 18147, 46901, 122403, 317379, 820951, 2131357, 5532371, 14340367, 37190407, 96488757, 250257339, 649031555, 1683483587, 4366629269, 11325556739, 29375297911, 76192462975, 197622279245 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304848.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-2) +8*a(n-3) +a(n-4) -9*a(n-5) -26*a(n-6) -6*a(n-7) +6*a(n-8) +16*a(n-9) +2*a(n-10) +6*a(n-11) for n>12

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304848.

Sequence in context: A008264 A000297 A078618 * A062883 A008176 A009903

Adjacent sequences:  A304840 A304841 A304842 * A304844 A304845 A304846

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 19 2018

STATUS

approved

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Last modified September 22 02:03 EDT 2021. Contains 347605 sequences. (Running on oeis4.)