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**mobius2000** ok, so i am working on power series solutions to differential equations and need to get some things straight. after substituting into the in question differential equation the required power series derivatives, say there is an X^2 coefficient and i need to bring it inside one of the series; should the starting point for that series be decreased by two (because the power on X outside the series is 2 and is being added to the X^[n+s] term to make it X^[n+s+2])?

also, how do i type in formulas is there perchance a program to do this?