A056321 Number of primitive (aperiodic) reversible strings with n beads using exactly five different colors.

0, 0, 0, 0, 60, 900, 8400, 63000, 417120, 2551500, 14804700, 82764000, 450518460, 2404502100, 12646078140, 65771433000, 339165516120, 1737485731740, 8855359634100, 44952365429940, 227475768899460

Offset: 1

Author

Marks R. Nester

Keywords

• nonn

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

Cf. A056316.

Formula

Sum mu(d)*A056312(n/d) where d|n.