## zmudz one year ago Find a closed form for Sn=1⋅1!+2⋅2!+…+n⋅n!. for integer n≥1. Your response should have a factorial.

1. freckles

are you just looking to put it in sigma notation?

2. freckles

notice if you had 1+2+3+...+n this can be written as $\sum_{i=1}^{n}i$ notice if you had 1!+2!+3!+...+n! this can be written as $\sum_{i=1}^{n}i!$

3. freckles

anyways I hope this gives you an idea of how to write 1*1!+2*2!+...+n*n! in sigma notation