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A223434 Generalized Petersen graph (8,2) coloring a rectangular array: number of n X 2 0..15 arrays where 0..15 label nodes of a graph with edges 0,1 0,8 8,14 8,10 1,2 1,9 9,15 9,11 2,3 2,10 10,12 3,4 3,11 11,13 4,5 4,12 12,14 5,6 5,13 13,15 6,7 6,14 7,0 7,15 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph. 2
48, 256, 1376, 7424, 40160, 217600, 1180256, 6405888, 34782688, 188912640, 1026197344, 5575016704, 30289360608, 164570543616, 894181114976, 4858543170304, 26399224399840, 143442922485760, 779415220762976 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A223440.

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) - 11*a(n-2) - 16*a(n-3).

Empirical g.f.: 16*x*(3 - 8*x - 9*x^2) / (1 - 8*x + 11*x^2 + 16*x^3). - Colin Barker, Mar 16 2018

EXAMPLE

Some solutions for n=3:

..6..5....8..0....3..4...11.13....7..0...11.13....9..1....1..0....1..9....1..9

.14..6....0..7....2..3...13.15...15..7...13.15....1..2....0..1....2..1....9.11

..8.14....8..0....3..2...15.13....9.15...15..7....2..3....1..2....3..2....1..9

CROSSREFS

Cf. A223440.

Sequence in context: A052683 A206054 A206047 * A235911 A235904 A275406

Adjacent sequences:  A223431 A223432 A223433 * A223435 A223436 A223437

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 20 2013

STATUS

approved

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Last modified October 16 02:29 EDT 2021. Contains 348034 sequences. (Running on oeis4.)