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A303249 Number of nX3 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
1, 14, 49, 250, 1183, 5918, 28680, 141255, 691968, 3391358, 16627204, 81517689, 399591042, 1958997017, 9603668921, 47080079771, 230803211309, 1131476255863, 5546875012244, 27192677194545, 133307748424215, 653519804327678 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A303254.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +6*a(n-2) +7*a(n-3) -61*a(n-4) -78*a(n-5) +115*a(n-6) +26*a(n-7) -126*a(n-8) -300*a(n-9) +380*a(n-10) -80*a(n-11) +144*a(n-12) -32*a(n-13) +128*a(n-14)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303254.

Sequence in context: A084049 A251221 A302467 * A215569 A246973 A156192

Adjacent sequences:  A303246 A303247 A303248 * A303250 A303251 A303252

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 20 2018

STATUS

approved

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Last modified August 20 05:25 EDT 2019. Contains 326139 sequences. (Running on oeis4.)