A283108 Number of fixed polyominoes minus number of free polyominoes for order n.

0, 0, 1, 4, 14, 51, 181, 652, 2356, 8625, 31791, 118195, 442261, 1665299, 6302903, 23968090, 91513682, 350687935, 1348198490, 5198114444, 20094107710, 77860452105, 302340714990, 1176325327796, 4584989069865, 17900574971247, 69993587545033, 274071021159757, 1074577571232370

Offset: 0

Author

Francois Alcover, Feb 28 2017

Keywords

• nonn

Comments

a(n) is the number of fixed polyominoes that are a transform -- except through identity -- of a canonical polyomino.

E.g., n=3:

A001168

______|_________

| |

A000105 | A283108

canon | transform

|

* |

* |

* | * * *

|

* | * * * * *

* * | * * * *

Links

• John Mason, Table of n, a(n) for n = 0..50

Crossrefs

Cf. A000105, A001168.

Formula

a(n) = A001168(n) - A000105(n).