oo ____ \ ` \ / /2\ \ \ | tan|-| | / | \n/ | / \E - 1/ /___, n = 1
Sum(E^tan(2/n) - 1, (n, 1, oo))
oo ____ \ ` \ / /2\\ \ | tan|-|| / | \n/| / \-1 + e / /___, n = 1
Sum(-1 + exp(tan(2/n)), (n, 1, oo))
x^n/n
(x-1)^n
1/2^(n!)
n^2/n!
x^n/n!
k!/(n!*(n+k)!)
csc(n)^2/n^3
1/n^2
1/n^4
1/n^6
1/n
(-1)^n
(-1)^(n + 1)/n
(n + 2)*(-1)^(n - 1)
(3*n - 1)/(-5)^n
(-1)^(n - 1)*n/(6*n - 5)
(-1)^(n + 1)/n*x^n
(3*n - 1)/(-5)^n