# Not ordinary sum-2

Calculus Level 5

$\large \sum _{ n=1 }^{ \infty }{ \dfrac { { n }^{ 4} }{ { 4 }^{ n }\cdot n! } } =\dfrac { c~\sqrt [ a ]{ e } ~\pi^{d-1}}{ b }$

If the equation above holds true for positive integers $$a,b,c,d$$, with $$b, c$$ coprime, find $$a+b+c+d$$.

Clarification: $$e \approx 2.71828$$ denotes the Euler's number.

Try part-1 here.

×