A223214 3X3X3 triangular graph coloring a rectangular array: number of nX4 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,2 1,2 1,3 1,4 2,4 3,4 2,5 4,5 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

192, 6642, 254694, 9640008, 367156350, 13964418774, 531419938920, 20220127602030, 769404277676466, 29276398278326448, 1113995137856350842, 42388505934881462730, 1612921387627093865328, 61373120006749414194594

Offset

1,1

Comments

Column 4 of A223218

Links

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

Formula

Empirical: a(n) = 36*a(n-1) +219*a(n-2) -5538*a(n-3) +3051*a(n-4) +141678*a(n-5) -180657*a(n-6) -980802*a(n-7) +1136403*a(n-8) +1765044*a(n-9) -1679697*a(n-10) -991440*a(n-11) +763668*a(n-12) +60264*a(n-13) -77760*a(n-14) +7776*a(n-15)

Example

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

Crossrefs

Sequence in context: A223375 A233154 A292076 * A215688 A173783 A290178

Adjacent sequences: A223211 A223212 A223213 * A223215 A223216 A223217

Keyword

nonn

Author

R. H. Hardin Mar 18 2013

Status

approved