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A275140 Number of n X 6 0..2 arrays with no element equal to any value at offset (-2,-2) (-1,-2) or (0,-1) and new values introduced in order 0..2. 1
16, 432, 1216, 6464, 32384, 165568, 841536, 4283968, 21800000, 110943552, 564600384, 2873300800, 14622480448, 74415076672, 378704836160, 1927261993792, 9808004727872, 49913793159488, 254015655387712, 1292707868694336 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

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

Empirical g.f.: 16*x*(1 + 24*x - 15*x^2 - 98*x^3 - 52*x^4 + 40*x^5) / (1 - 3*x - 10*x^2 - 4*x^3 + 4*x^4). - Colin Barker, Jan 31 2019

EXAMPLE

Some solutions for n=5:

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

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

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

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

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

CROSSREFS

Column 6 of A275142.

Sequence in context: A220286 A322713 A275035 * A274731 A111921 A118994

Adjacent sequences:  A275137 A275138 A275139 * A275141 A275142 A275143

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 17 2016

STATUS

approved

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Last modified October 24 20:35 EDT 2021. Contains 348233 sequences. (Running on oeis4.)