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A318217 Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
0, 1, 4, 18, 86, 413, 1975, 9474, 45415, 217714, 1043722, 5003565, 23986950, 114992767, 551272103, 2642783040, 12669427963, 60736883262, 291170919400, 1395865242913, 6691738929130, 32080009243747, 153790666966961 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 3 of A318222.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -a(n-2) +a(n-3) -5*a(n-4) +3*a(n-5) -3*a(n-6) +a(n-7) -8*a(n-8) -4*a(n-10) +2*a(n-11)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A318222.

Sequence in context: A055834 A079567 A030278 * A151252 A084847 A082685

Adjacent sequences:  A318214 A318215 A318216 * A318218 A318219 A318220

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 21 2018

STATUS

approved

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Last modified April 19 19:07 EDT 2019. Contains 322290 sequences. (Running on oeis4.)