Let ${a_n} = \int\limits_{ - 1}^n {\left( {1 + {x \over 2} + {{{x^2}} \over 3} + \,\,.....\,\, + \,\,{{{x^{n - 1}}} \over n}} \right)dx} $ for every n $\in$ N. Then the sum of all the elements of the set {n $\in$ N : an $\in$ (2, 30)} is ____________.

Question

Let ${a_n} = \int\limits_{ - 1}^n {\left( {1 + {x \over 2} + {{{x^2}} \over 3} + \,\,.....\,\, + \,\,{{{x^{n - 1}}} \over n}} \right)dx} $ for every n $\in$ N. Then the sum of all the elements of the set {n $\in$ N : a_n $\in$ (2, 30)} is ____________.

Correct Answer

Solution

Please login to view the detailed solution steps...

Go to DASH