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A275353 Number of 3Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2. 1
5, 54, 288, 1536, 8192, 43712, 235072, 1264832, 6809856, 36666496, 197447168, 1063304448, 5726352128, 30839264512, 166086172928, 894467665408, 4817222467584, 25943536156672, 139721052861440, 752479440667648 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A275352.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -2*a(n-2) -8*a(n-3) +20*a(n-4) -44*a(n-5) -160*a(n-6) -180*a(n-7) +152*a(n-8) -880*a(n-9) -928*a(n-10) +848*a(n-11) +816*a(n-12) +2752*a(n-13) +2880*a(n-14) +2560*a(n-15) -2048*a(n-16) -4096*a(n-18) for n>20

EXAMPLE

Some solutions for n=4

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

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

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

CROSSREFS

Cf. A275352.

Sequence in context: A275396 A275261 A208429 * A221544 A268882 A229298

Adjacent sequences:  A275350 A275351 A275352 * A275354 A275355 A275356

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 24 2016

STATUS

approved

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Last modified December 2 14:09 EST 2021. Contains 349445 sequences. (Running on oeis4.)