cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A091268 Number of orbits of length n under the map whose periodic points are counted by A061685.

Original entry on oeis.org

1, 4, 99, 6272, 876725, 232419936, 105471170140, 76095730062464, 82555139387847312, 128928209221144677400, 279860608037771819829980, 820360089598849358326307904, 3169977309466844379463315722484
Offset: 1

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Author

Thomas Ward, Feb 24 2004

Keywords

Comments

Old name was: A061685 appears to count the periodic points for a certain map. If so, then this is the sequence of the numbers of orbits of length n for that map.

Examples

			b(1)=1, b(2)=9, b(3)=298. Hence a(3)=(1/3)(b(3)-b(1))=99.
		

Crossrefs

Cf. A061685.

Formula

If b(n) is the (n+1)th term of A061685, then a(n) = (1/n)*Sum_{d|n}mu(d)b(n/d).

Extensions

Name clarified by Michel Marcus, May 14 2015