A223252 Two-loop graph coloring a rectangular array: number of nX5 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

208, 4908, 166892, 5359892, 200258884, 6581646956, 247417877452, 8146965446276, 306270743418628, 10089859264898796, 379171102402141516, 12496512099428874724, 469428050069027239844, 15477220252232343414028

Offset

1,1

Comments

Column 5 of A223255

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +1287*a(n-2) -8754*a(n-3) -66498*a(n-4) +293943*a(n-5) +1110271*a(n-6) -2420678*a(n-7) -6380827*a(n-8) +7393360*a(n-9) +14420088*a(n-10) -8685630*a(n-11) -12202500*a(n-12) +3405276*a(n-13) +3205824*a(n-14) -279936*a(n-15) -165888*a(n-16)

Example

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

Crossrefs

Sequence in context: A343507 A231111 A339762 * A223610 A184276 A268091

Adjacent sequences: A223249 A223250 A223251 * A223253 A223254 A223255

Keyword

nonn

Author

R. H. Hardin Mar 18 2013

Status

approved