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A318070 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
4, 10, 18, 41, 81, 179, 404, 893, 2000, 4516, 10125, 22737, 51181, 115034, 258515, 581380, 1307094, 2938317, 6606445, 14853275, 33392840, 75076165, 168791772, 379483956, 853176349, 1918162541, 4312510121, 9695613622, 21798217755 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A318075.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-3) -3*a(n-4) -6*a(n-5) +6*a(n-6) for n>10

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A318075.

Sequence in context: A009913 A063591 A009912 * A073262 A145731 A162958

Adjacent sequences:  A318067 A318068 A318069 * A318071 A318072 A318073

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 15 2018

STATUS

approved

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Last modified April 7 10:00 EDT 2020. Contains 333300 sequences. (Running on oeis4.)