A222276 Number of n X 3 0..5 arrays with no entry increasing mod 6 by 5 rightwards or downwards, starting with upper left zero.

25, 2205, 194485, 17153945, 1513010465, 133450391205, 11770577485085, 1038187247574145, 91570083319317865, 8076654937439905005, 712376276332499775685, 62832938018547611186345, 5541984245134992804289265

Offset

1,1

Comments

Column 3 of A222281.

Links

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

Formula

Empirical: a(n) = 92*a(n-1) - 335*a(n-2).

Conjectures from Colin Barker, Mar 14 2018: (Start)

G.f.: 5*x*(5 - 19*x) / (1 - 92*x + 335*x^2).

a(n) = ((46-sqrt(1781))^n*(-801+19*sqrt(1781)) + (46+sqrt(1781))^n*(801+19*sqrt(1781))) / (134*sqrt(1781)).

(End)

Example

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

Crossrefs

Cf. A222281.

Sequence in context: A195272 A266130 A363192 * A304323 A135057 A324417

Adjacent sequences: A222273 A222274 A222275 * A222277 A222278 A222279

Keyword

nonn

Author

R. H. Hardin, Feb 14 2013

Status

approved