A223505 Petersen graph (3,1) coloring a rectangular array: number of 2 X n 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0.

6, 19, 115, 631, 3539, 19759, 110427, 617015, 3447747, 19265087, 107648363, 601511175, 3361088979, 18780896143, 104942791931, 586393188311, 3276613524707, 18308869209055, 102305227390859, 571655159691687

Offset

1,1

Comments

Row 2 of A223504.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) + 4*a(n-2) - 4*a(n-3) for n>4.

Empirical g.f.: x*(2 - x)*(1 - 2*x)*(3 + 2*x) / (1 - 5*x - 4*x^2 + 4*x^3). - Colin Barker, Aug 21 2018

Example

Some solutions for n=3:
..0..1..0....0..3..0....0..2..0....0..2..1....0..2..1....0..1..4....0..1..0
..0..1..4....5..3..5....5..2..5....1..2..0....0..2..0....4..1..0....2..1..0

Crossrefs

Cf. A223504.

Sequence in context: A285853 A138748 A097899 * A054236 A118411 A091876

Adjacent sequences: A223502 A223503 A223504 * A223506 A223507 A223508

Keyword

nonn

Author

R. H. Hardin, Mar 21 2013

Status

approved