A222336 Number of n X 3 0..6 arrays with no entry increasing mod 7 by 6 rightwards or downwards, starting with upper left zero.

36, 5766, 923526, 147918906, 23691810366, 3794659477146, 607781352505806, 97346856728146986, 15591808593304758846, 2497301950787699442426, 399986762028752524653486, 64064904024834487199387466

Offset: 1

Author

R. H. Hardin, Feb 15 2013

Keywords

• nonn

Comments

Column 3 of A222340.

Examples

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

Links

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

Crossrefs

Cf. A222340

Formula

Empirical: a(n) = 165*a(n-1) - 774*a(n-2).

Empirical g.f.: 6*x*(6 - 29*x) / (1 - 165*x + 774*x^2). - Colin Barker, Mar 15 2018