A220124 Number of tilings of a 6 X n rectangle using integer-sided rectangular tiles of area 6.

1, 1, 2, 4, 7, 13, 46, 88, 209, 473, 1002, 2120, 5197, 11085, 25384, 57234, 126959, 279883, 640387, 1412460, 3182794, 7138463, 15963680, 35593612, 80143244, 178644947, 400681480, 897313564, 2008904252, 4492651815, 10074017008, 22526314856, 50459193392

Offset: 0

Author

Alois P. Heinz, Dec 05 2012

Keywords

• nonn

Examples

			a(4) = 7, because there are 7 tilings of a 6 X 4 rectangle using integer-sided rectangular tiles of area 6:
._._._._. ._._._._. ._._._._. ._._._._. ._._._._. ._._._._. ._._._._.
| | | | | |   | | | | |   | | | | |   | |   |   | |     | | | |     |
| | | | | |   | | | | |   | | | | |   | |   |   | |     | | | |     |
| | | | | |___| | | | |___| | | | |___| |___|___| |_____| | | |_____|
| | | | | |   | | | | |   | | | | |   | |   |   | |     | | | |     |
| | | | | |   | | | | |   | | | | |   | |   |   | |     | | | |     |
|_|_|_|_| |___|_|_| |_|___|_| |_|_|___| |___|___| |_____|_| |_|_____|
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..1000

Crossrefs

Column k=6 of A220122.