Lattice word

In mathematics, a lattice word (or lattice permutation) is a string composed of positive integers, in which every prefix contains at least as many positive integers i as integers i + 1.

A reverse lattice word, or Yamanouchi word, is a string whose reversal is a lattice word.

Examples

For instance, 11122121 is a lattice permutation, so 12122111 is a Yamanouchi word, but 12122111 is not a lattice permutation, since the sub-word 12122 contains more two's than one's.

gollark: You want it to capacitate, but not too much.
gollark: Yes it does. Smaller things can sometimes be harder to make.
gollark: Oh please, like I use *electromagnetism* for critical computations.
gollark: Of course we do.
gollark: We just do light in software instead.

See also

  • Dyck word

References

  • Fulton, William (1997), Young tableaux, London Mathematical Society Student Texts, 35, Cambridge University Press, ISBN 978-0-521-56724-4, MR 1464693
  • Macdonald, Ian G. (1995), Symmetric functions and Hall polynomials, Oxford Mathematical Monographs (Second ed.), The Clarendon Press and Oxford University Press, ISBN 0-19-853489-2, MR 1354144
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.