A220773 Number of tilings of a 7 X n rectangle using integer-sided rectangular tiles of equal area.

1, 2, 24, 12, 850, 7, 31777, 4, 1300180, 2877, 53175580, 9, 2189911837, 11, 90124167476, 972776, 3710809418140, 25, 152783310505831, 38, 6290664383805343, 329097191, 259009513044646014, 86, 10664385331038730694, 8709, 439092316687230373634, 111328277385

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..300

Example

a(5) = 7:
._________.  ._________.  ._________.  ._________.
|         |  | | | | | |  |_________|  |_________|
|         |  | | | | | |  |_________|  | | | | | |
|         |  | | | | | |  | | | | | |  | | | | | |
|         |  | | | | | |  | | | | | |  | | | | | |
|         |  | | | | | |  | | | | | |  | | | | | |
|         |  | | | | | |  | | | | | |  |_|_|_|_|_|
|_________|  |_|_|_|_|_|  |_|_|_|_|_|  |_________|
._________.  ._________.  ._________.
| | | | | |  |_________|  |_|_|_|_|_|
| | | | | |  |_________|  |_|_|_|_|_|
| | | | | |  |_________|  |_|_|_|_|_|
| | | | | |  |_________|  |_|_|_|_|_|
|_|_|_|_|_|  |_________|  |_|_|_|_|_|
|_________|  |_________|  |_|_|_|_|_|
|_________|  |_________|  |_|_|_|_|_|

Crossrefs

Column k=7 of A220777.

Sequence in context: A278563 A075267 A002743 * A290772 A342545 A055535

Adjacent sequences: A220770 A220771 A220772 * A220774 A220775 A220776

Keyword

nonn

Author

Alois P. Heinz, Dec 19 2012

Status

approved