A229584 Number of defective 3-colorings of an n X 6 0..2 array connected horizontally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..2 order.

40, 1620, 49848, 1375152, 35690460, 890824020, 21639043284, 515235810840, 12081465854052, 279877517457936, 6420164883723960, 146080173897129444, 3301145304079911108, 74165789377610689020, 1657889614174445634696

Offset

1,1

Links

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

Formula

Empirical: a(n) = 50*a(n-1) - 805*a(n-2) + 4662*a(n-3) - 12150*a(n-4) + 14580*a(n-5) - 6561*a(n-6).

Empirical g.f.: 4*x*(10 - 95*x + 262*x^2 + 93*x^3 - 1485*x^4 + 1701*x^5) / (1 - 25*x + 90*x^2 - 81*x^3)^2. - Colin Barker, Sep 19 2018

Example

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

Crossrefs

Column 6 of A229586.

Sequence in context: A041761 A229635 A278431 * A140702 A223609 A145294

Adjacent sequences: A229581 A229582 A229583 * A229585 A229586 A229587

Keyword

nonn

Author

R. H. Hardin, Sep 26 2013

Status

approved