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[Emeric Deutsch]

Dear Maple wizards,

I have a Maple problem:
The command 
g:=solve(F-1-z*F^3*(F-1+t),F); series(g,z=0,8);
yields very nicely
1 + tz + t(3t+1)z^2 + t(1+9t+12t^2)z^3 + ...

However, if I replace the equation in F by one of
degree 3, for example, F-1-z*F^2*(F-1+t), then the
command

g:=solve(F-1-z*F^2*(F-1+t),F); series(g,z=0,8);

gets stuck.

The actual equation I am presently interested in is:

z^2*G^3-z*(2+t*z-2*z)*G^2+(1+t*z^2-2*z^2)*G-1+z;

Many thanks,
Emeric