A086832 Number of ways to tile an n X n board having a black border with the following 1 X 1 tiles: bbbb, bbww, wbbw, bwwb, wwbb, where the colors are read clockwise around each tile.

1, 2, 5, 36, 324, 7041, 233265, 16038658, 1884307184, 426645198097, 173238487743952

Offset

1,2

Comments

A valid tiling is one in which black touches black and white touches white.

Links

Table of n, a(n) for n=1..11.

Crossrefs

Sequence in context: A160968 A329704 A275552 * A317801 A111491 A331402

Adjacent sequences: A086829 A086830 A086831 * A086833 A086834 A086835

Keyword

nonn

Author

Aaron M. Balog (ambalog(AT)ucdavis.edu), Aug 07 2003

Status

approved