A229571 Number of defective 4-colorings of an n X n 0..3 array connected horizontally, vertically, diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..3 order.

0, 6, 76, 312, 924, 2440, 6108, 14840, 35356, 83016, 192636, 442552, 1007868, 2277704, 5112220, 11403768, 25297500, 55837384, 122684220, 268436408, 585106492

Offset

1,2

Comments

Diagonal of A229578.

Links

Table of n, a(n) for n=1..21.

Formula

Empirical (for n>=9): a(n) = 9*a(n-1) - 33*a(n-2) + 63*a(n-3) - 66*a(n-4) + 36*a(n-5) - 8*a(n-6). - Vaclav Kotesovec, Feb 14 2014

Example

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

Crossrefs

Cf. A229578.

Sequence in context: A350283 A350411 A263228 * A016090 A181343 A241072

Adjacent sequences: A229568 A229569 A229570 * A229572 A229573 A229574

Keyword

nonn

Author

R. H. Hardin, Sep 26 2013

Status

approved