A223244 3-loop graph coloring a rectangular array: number of nX5 0..6 arrays where 0..6 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

528, 26034, 2663082, 198634758, 22029652542, 1657797796530, 184125991023066, 13859263865786022, 1539229991488330446, 115867585607831455650, 12867476965518013727850, 968688138419572520572470

Offset

1,1

Comments

Column 5 of A223247

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +8457*a(n-2) -75674*a(n-3) -827914*a(n-4) +4950877*a(n-5) +19716867*a(n-6) -72423910*a(n-7) -171181013*a(n-8) +357711566*a(n-9) +599583056*a(n-10) -618648196*a(n-11) -759861052*a(n-12) +283902208*a(n-13) +238368720*a(n-14) -20743200*a(n-15) -9720000*a(n-16)

Example

Some solutions for n=3
..5..0..1..0..6....5..0..5..0..2....3..0..4..0..3....1..0..3..0..3
..0..1..0..4..0....0..1..0..3..0....0..5..0..4..0....0..3..0..4..0
..3..0..1..0..5....3..0..4..0..1....3..0..5..0..4....3..0..3..0..4

Crossrefs

Sequence in context: A282096 A223253 A233103 * A059465 A071236 A048101

Adjacent sequences: A223241 A223242 A223243 * A223245 A223246 A223247

Keyword

nonn

Author

R. H. Hardin Mar 18 2013

Status

approved