# How to work with the inverse of finite difference on WolframAlpha?

Im taking a course of Discrete Math, we are working with "finite calculus".

In Wolfram the discrete derivative is for example the differencedelta(2^x,x) function, but i want the inverse, the sum: $\sum(2x)dx$. How to compute that in Wolfram ?

Alternatively, any software with good support for discrete math?

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