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A304217 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3 or 8 king-move adjacent elements, with upper left element zero. 1
5, 17, 17, 32, 62, 108, 190, 348, 636, 1152, 2082, 3768, 6840, 12412, 22486, 40744, 73872, 133932, 242782, 440076, 797732, 1446128, 2621506, 4752084, 8614284, 15615592, 28307242, 51313936, 93019232, 168620580, 305667118, 554098192 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A304221.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-3) +a(n-4) +a(n-5) -2*a(n-7) for n>9

EXAMPLE

Some solutions for n=7

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

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

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

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

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

CROSSREFS

Cf. A304221.

Sequence in context: A237437 A128895 A141558 * A305248 A231710 A316548

Adjacent sequences:  A304214 A304215 A304216 * A304218 A304219 A304220

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 08 2018

STATUS

approved

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Last modified July 24 09:52 EDT 2021. Contains 346273 sequences. (Running on oeis4.)