**Charles Fefferman, Interpolation of C^m Functions in n
dimensions
**

Fix positive integers m,n. Given points x1,...,xN in R^n, and given

real numbers y1,...,yN, we compute efficiently a function F in C^m

(R^n),such that F(xk)=yk for each k, with the C^m norm of F having

the least possible order of magnitude.

We consider also several variants of the above problem.

(Joint work with Bo'az Klartag.)