# A sum involving binomial coefficient

1. Jul 22, 2010

### zh3f

$$sum_{i=k}^{n} {i \choose k}i^{-t}$$

where t is a constant.

Does it have a closed form?

Last edited: Jul 22, 2010
2. Jul 27, 2010

### Eynstone

A closed form is possible only for integral values of t (that too, if you can solve the differential equation involving the generating function).