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.

A056316 Number of primitive (aperiodic) reversible strings with n beads using a maximum of five different colors.

Original entry on oeis.org

5, 10, 70, 310, 1620, 7790, 39370, 195300, 978050, 4882740, 24421870, 122069940, 610390620, 3051757490, 15258982680, 76293945000, 381470703120, 1907348623450, 9536748046870, 47683715818440
Offset: 1

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Keywords

Comments

A string and its reverse are considered to be equivalent.

References

  • M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]

Crossrefs

Column 5 of A284871.
Cf. A045625.

Formula

Sum mu(d)*A032122(n/d) where d|n.