@Preben Alsholm 

i tried to pdsolve but it gave solutions depend on (x,t). But i want to solve u0,u1,.. depend on f(x,t). 

@tomleslie i wanted to find lambda symmetries, integrating factors, linearization transformations for ordinary differential equations but it did not.

thanks for your effort

it works 2+2 and  4*5,  but diff(x,x) not work. i installed  fully. what is the maple's kernel problem? how can i solve it.