A030444 Number of fixed n-celled polyknights.

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

Offset

1,2

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.

Links

Table of n, a(n) for n=1..13.

Crossrefs

Cf. A030445, A030446, A030447, A030448.

Sequence in context: A307468 A202824 A046904 * A093877 A151830 A354693

Adjacent sequences: A030441 A030442 A030443 * A030445 A030446 A030447

Keyword

nonn,more

Author

David W. Wilson

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

Status

approved