oo ___ \ ` \ /cos(2*n)*x 2 \ ) |----------*n - 1| / \ 4 / /__, n = 1
Sum(((cos(2*n)*x)/4)*n^2 - 1, (n, 1, oo))
oo ____ \ ` \ / 2 \ \ | x*n *cos(2*n)| / |-1 + -------------| / \ 4 / /___, n = 1
Sum(-1 + x*n^2*cos(2*n)/4, (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