A229602 Number of defective 3-colorings of an n X 4 0..2 array connected horizontally and vertically with exactly two mistakes, and colors introduced in row-major 0..2 order.

3, 202, 3040, 35182, 362100, 3476928, 31848813, 281845934, 2429033768, 20498682291, 170050970491, 1390738347774, 11237781105036, 89873465482971, 712350529942518, 5602092417764388, 43752038622648030, 339600817518201684

Offset

1,1

Comments

Column 4 of A229606.

Links

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

Formula

Empirical: a(n) = 27*a(n-1) - 288*a(n-2) + 1557*a(n-3) - 4644*a(n-4) + 8073*a(n-5) - 8343*a(n-6) + 5022*a(n-7) - 1620*a(n-8) + 216*a(n-9) for n > 11.

Example

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

Crossrefs

Cf. A229606.

Sequence in context: A264674 A306630 A140654 * A080297 A080274 A076531

Adjacent sequences: A229599 A229600 A229601 * A229603 A229604 A229605

Keyword

nonn

Author

R. H. Hardin, Sep 26 2013

Status

approved