I am struggling to find an answer of the following series
$\sum_{i=1}^n \frac{1}{1+\exp(a_i+b_ix)}$
Any suggestion?
sequences-and-series
asked 2012-10-05
user id:43720
26
11bronze badges
0
You won't be able to. For an example, let all the $b_i$ be zero. Compare $a_1=a_2=5$ to $a_1=0, a_2=10$ These are not equal, but your expression cannot tell them apart. – 2012-10-05