Answer
common difference = $1$
The first four terms are: $1, 2, 3, 4$
Work Step by Step
To find the first four terms, substitute $1, 2, 3, 4$ for $n$ in the given formula; then, use the rule $e^{(\ln{n})} = n$ to simplify.
$s_1 = e^{\ln{1}} = 1$
$s_2= e^{\ln{2}}=2$
$s_3 = e^{\ln3} = 3$
$s_4 = e^{\ln4}=4$
The terms increase by $1$ unit, so the sequence is arithmetic with a common difference of $1$.
