A229691 Number of defective 3-colorings of an nX5 0..2 array connected horizontally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..2 order

12, 1171, 35825, 848937, 17724789, 342532665, 6279934941, 110801828529, 1898544262293, 31786996628745, 522316663574733, 8450380115641377, 134940473888031045, 2130891564532483449, 33326706458497564413

Offset

1,1

Comments

Column 5 of A229694

Links

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

Formula

Empirical: a(n) = 45*a(n-1) -729*a(n-2) +4995*a(n-3) -13122*a(n-4) +14580*a(n-5) -5832*a(n-6) for n>7.

Empirical: 12*x -x^2*(-1171+16870*x-90471*x^2+210096*x^3-212220*x^4+81648*x^5) / (18*x^2-15*x+1)^3. - R. J. Mathar, Sep 29 2013

Example

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

Crossrefs

Sequence in context: A091782 A291952 A112580 * A180586 A178529 A360502

Adjacent sequences: A229688 A229689 A229690 * A229692 A229693 A229694

Keyword

nonn

Author

R. H. Hardin, Sep 27 2013

Status

approved