A030444 Number of fixed n-celled polyknights.

1, 4, 28, 234, 2162, 20972, 209608, 2135572, 22049959, 229939414, 2416816416, 25569786440, 272057195864

Offset: 1

Author

David W. Wilson

Keywords

• nonn
• more

Comments

A polyknight is a variant of a polyomino in which two tiles a knight's move apart are considered adjacent. A polyknight need not be connected in the sense of a polyomino.

References

• G. Aleksandrowicz and G. Barequet, Parallel enumeration of lattice animals, Proc. 5th Int. Frontiers of Algorithmics Workshop, Zhejiang, China, Lecture Notes in Computer Science, 6681, Springer-Verlag, 90-99, May 2011.

Crossrefs

Cf. A030445, A030446, A030447, A030448.

Extensions

Corrected and extended by Guenter Stertenbrink (Sterten(AT)aol.com), May 23 2004

12th term from Gill Barequet, May 24 2011

a(13) from John Mason, Jan 13 2023