A229576 Number of defective 4-colorings of an n X 6 0..3 array connected horizontally, vertically, diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..3 order.

70, 544, 757, 1064, 1576, 2440, 4048, 7224, 13696, 27080, 54928, 112984, 234016, 486120, 1010608, 2100344, 4361536, 9047560, 18747088, 38801304, 80220256, 165679400, 341840368, 704647864, 1451234176, 2986349640, 6140466448

Offset

1,1

Links

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

Formula

Empirical: a(n) = 6*a(n-1) - 13*a(n-2) + 12*a(n-3) - 4*a(n-4) for n>7.

Empirical g.f.: x*(70 + 124*x - 1597*x^2 + 2754*x^3 - 1215*x^4 - 92*x^5 + 156*x^6) / ((1 - x)^2*(1 - 2*x)^2). - Colin Barker, Sep 19 2018

Example

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

Crossrefs

Column 6 of A229578.

Sequence in context: A007330 A060541 A235302 * A234556 A183715 A104475

Adjacent sequences: A229573 A229574 A229575 * A229577 A229578 A229579

Keyword

nonn

Author

R. H. Hardin, Sep 26 2013

Status

approved