A bijection for the convolution of central binomial coefficients

Description:  All known bijective proofs for the convolution of central binomial coefficients $\sum_{i+j=n} \binom{2i}{i} \binom{2j}{j} = 4^n$,are based, with some variations, on the count of lattice paths. In this talk we give a new proof of this identity, where $\binom{2 \ell}{\ell}$ is regarded as the number of $\ell$-subsets of a $2 \ell$-subset. This is a joint work with António Guedes de Oliveira. Date:  2013-05-29 Start Time:   15:00 Speaker:  Rui Duarte (Univ. Aveiro) Institution:  Universidade de Aveiro Place:  Room 5.5 (DMUC) Research Groups: -Algebra and Combinatorics See more:   <Main>