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A275261 Number of nX3 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-1) and new values introduced in order 0..2. 1
5, 54, 128, 396, 1440, 5676, 22844, 93968, 389820, 1626348, 6799728, 28470780, 119289068, 500005184, 2096208716, 8789088828, 36853587936, 154536271820, 648021215772, 2717393443696, 11395105468828, 47784338066636 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A275266.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -4*a(n-2) -20*a(n-3) +28*a(n-4) -40*a(n-5) +8*a(n-6) +194*a(n-7) -180*a(n-8) +36*a(n-9) +56*a(n-10) -356*a(n-11) +201*a(n-12) +180*a(n-13) -108*a(n-14) for n>17

EXAMPLE

Some solutions for n=4

..0..1..1. .0..1..2. .0..1..2. .0..1..2. .0..1..0. .0..1..2. .0..1..0

..1..2..2. .0..1..0. .2..1..2. .2..2..0. .0..1..0. .0..1..0. .0..2..0

..2..2..0. .2..1..0. .0..1..2. .0..1..0. .2..1..2. .2..1..2. .0..2..0

..0..0..1. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .2..1..0. .1..2..1

CROSSREFS

Cf. A275266.

Sequence in context: A129664 A275499 A275396 * A208429 A275353 A221544

Adjacent sequences:  A275258 A275259 A275260 * A275262 A275263 A275264

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 21 2016

STATUS

approved

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Last modified December 2 19:57 EST 2021. Contains 349445 sequences. (Running on oeis4.)