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A304305 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3 or 5 king-move adjacent elements, with upper left element zero. 1
4, 23, 77, 261, 918, 3270, 11739, 42286, 152593, 551277, 1992676, 7204835, 26054060, 94223657, 340770353, 1232459982, 4457471732, 16121551990, 58307765439, 210885454206, 762723638858, 2758595178785, 9977203623515, 36085252551736 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304310.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +a(n-2) -6*a(n-3) -11*a(n-4) +2*a(n-5) +14*a(n-6) -6*a(n-7) -7*a(n-8) +15*a(n-9) +22*a(n-10) -6*a(n-11) -7*a(n-12) +a(n-13) +3*a(n-14) -10*a(n-15) -8*a(n-16)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304310.

Sequence in context: A226342 A071246 A219933 * A316204 A305771 A219465

Adjacent sequences:  A304302 A304303 A304304 * A304306 A304307 A304308

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 10 2018

STATUS

approved

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Last modified November 13 20:57 EST 2019. Contains 329106 sequences. (Running on oeis4.)