A229693 Number of defective 3-colorings of an n X 7 0..2 array connected horizontally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..2 order.

120, 20691, 1400413, 75035643, 3583403667, 159377253183, 6749642728251, 275739382892979, 10957241965280031, 425954258229381831, 16265054107660003947, 611918047133484899067, 22734198484723715670855

Offset

1,1

Comments

Column 7 of A229694.

Links

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

Formula

Empirical: a(n) = 126*a(n-1) - 6345*a(n-2) + 165456*a(n-3) - 2474469*a(n-4) + 22918302*a(n-5) - 138045627*a(n-6) + 554666940*a(n-7) - 1494608922*a(n-8) + 2659094568*a(n-9) - 2986698420*a(n-10) + 1913187600*a(n-11) - 531441000*a(n-12) for n > 14.

Example

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

Crossrefs

Sequence in context: A268474 A363516 A289566 * A105188 A264957 A270604

Adjacent sequences: A229690 A229691 A229692 * A229694 A229695 A229696

Keyword

nonn

Author

R. H. Hardin, Sep 27 2013

Status

approved