A223410 4X4X4 triangular graph without horizontal edges coloring a rectangular array: number of nX3 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

66, 780, 10496, 139552, 1905248, 25615364, 350374768, 4718334196, 64553618848, 869537910656, 11896879751308, 160257988295804, 2192633026299036, 29536279905976948, 404112522712546100, 5443681701489022792

Offset

1,1

Comments

Column 3 of A223415

Links

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

Formula

Empirical: a(n) = 246*a(n-2) -12495*a(n-4) +213864*a(n-6) -1242839*a(n-8) +3210236*a(n-10) -3946254*a(n-12) +2244580*a(n-14) -563760*a(n-16) +50544*a(n-18) for n>19

Example

Some solutions for n=3
..2..4..8....1..4..2....8..4..2....4..2..4....1..0..2....5..9..5....4..2..4
..0..2..5....4..8..4....5..2..5....7..4..2....4..1..0....8..5..9....7..4..1
..2..0..2....2..4..1....8..5..9....4..1..4....2..4..1....5..9..5....3..1..4

Crossrefs

Sequence in context: A128952 A282050 A270258 * A258917 A223152 A301544

Adjacent sequences: A223407 A223408 A223409 * A223411 A223412 A223413

Keyword

nonn

Author

R. H. Hardin Mar 20 2013

Status

approved