A223694 Petersen graph (8,2) coloring a rectangular array: number of 3Xn 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 antidiagonal neighbor moves along an edge of this graph

4096, 3888, 37008, 363600, 3788640, 40075632, 427910688, 4599435024, 49661922528, 537886587312, 5838098127264, 63455538372048, 690372511036128, 7515830878003440, 81857442742673184, 891795388496947344

Offset

1,1

Comments

Row 3 of A223692

Links

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

Formula

Empirical: a(n) = 13*a(n-1) +15*a(n-2) -391*a(n-3) -399*a(n-4) +1739*a(n-5) +205*a(n-6) -2013*a(n-7) +580*a(n-8) +396*a(n-9) -144*a(n-10) for n>12

Example

Some solutions for n=3
.15..7..0...11..3..4....5.13.15....0..1..0....9.11.13...15.13.15....7..6..7
.15..7.15...11..3..4....5.13..5....0..1..0...13..5..6....5.13.15....7.15.13
.15..7..6...11..3..4....5.13.11....0..1..2....6..5..6...15..9..1....9.11.13

Crossrefs

Sequence in context: A176768 A223601 A186490 * A186489 A221261 A069273

Adjacent sequences: A223691 A223692 A223693 * A223695 A223696 A223697

Keyword

nonn

Author

R. H. Hardin Mar 25 2013

Status

approved