Abstract
In this paper we consider formal solutions of the following form for some linear partial differential equations: $\hat{u}$(t,x) = Σi≥1 Σk≤miui,k(x)ti(log t)k. Under the same conditions as those in Ōuchi [8], we show multisummability of the formal solutions $\hat{u}$(t,x). It is our key of proofs to find a solution of exponential growth for convolution equations with polynomial coefficients with respect to y via the change of variable log t = y.
