A combinatorial survey of identities for the double factorial
Combinatorics
2009-06-09 v1
Abstract
We survey combinatorial interpretations of some dozen identities for the double factorial such as, for instance, (2n-2)!! + Sum_{k=2}^{n} (2n-1)!!(2k-4)!!/(2k-1)!! = (2n-1)!!. Our methods are mostly bijective.
Cite
@article{arxiv.0906.1317,
title = {A combinatorial survey of identities for the double factorial},
author = {David Callan},
journal= {arXiv preprint arXiv:0906.1317},
year = {2009}
}
Comments
29 pages