A206629 Number of (n+1) X 3 0..2 arrays with every 2 X 3 or 3 X 2 subblock having no more than four equal edges, and new values 0..2 introduced in row major order.

121, 3232, 86392, 2309200, 61723264, 1649819344, 44098506880, 1178721971776, 31506406571584, 842144015978368, 22509915310006528, 601674152698239232, 16082325545854547968, 429869213764553543680, 11490100757858808902656

Offset

1,1

Comments

Column 2 of A206635.

Links

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

Formula

Empirical: a(n) = 24*a(n-1) + 68*a(n-2) + 132*a(n-3) + 8*a(n-4) + 48*a(n-5).

Empirical g.f.: x*(121 + 328*x + 596*x^2 + 44*x^3 + 216*x^4) / (1 - 24*x - 68*x^2 - 132*x^3 - 8*x^4 - 48*x^5). - Colin Barker, Jun 17 2018

Example

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

Crossrefs

Cf. A206635.

Sequence in context: A232021 A231751 A264495 * A014758 A069600 A244065

Adjacent sequences: A206626 A206627 A206628 * A206630 A206631 A206632

Keyword

nonn

Author

R. H. Hardin, Feb 10 2012

Status

approved