Renormings of Lp(Lq)
We investigate the best order of smoothness of Lp(Lq). We prove in particular that there exists a [script C][infty infinity]-smooth bump function on Lp(Lq) if and only if p and q are even integers and p is a multiple of q.(Received July 3 1997)
(Revised March 11 1998)
1 The research of the second and third authors was partially supported by DGICYT grant PB 93-0452.