New posts in sequences-and-series

Does $\sum_{k=0}^{\infty}\sin\left(\frac{\pi x}{2^k}\right)$ have a simple form with interesting properties?

Find the 8th derivative of the function $h(x) = xe^x $using sequences

Is the sequence defined by the recurrence $ a _ { n + 2 } = \frac 1 { a _ { n + 1 } } + \frac 1 { a _ n } $ convergent? [duplicate]

Calculating $\sqrt{-1}$

Closed form solution for the zeros of an infinite sum

A theorem about Cesàro mean, related to Stolz-Cesàro theorem

Kummer's test - Calculus, Apostol, 10.16 #15.

Why is the ratio test for $L=1$ inconclusive?

Limit of the sequence $a_{n+1}=\frac{1}{2} (a_n+\sqrt{\frac{a_n^2+b_n^2}{2}})$ - can't recognize the pattern

Finding the sum $\sum\limits_{n=1,n\neq m^2}^{1000}\left[\frac{1}{\{\sqrt{n}\}}\right]$,

Sum of cosines of primes

Prove that $a_n=(-1)^n$ does not converge

Suppose $a_n \ge 0$ for all n and that $\sum_{n=1}^{\infty} (a_n)^2$ converges, does the $\sum_{n=1}^{\infty} a_n$ also converge?

Proving a number defined by a sequence is a square number

How to find finite trigonometric products [closed]

Closed form for $a_{n+1} = (a_n)^2+\frac{1}{4}$

Formal (series/sum/derivative...)

Sums in $\mathbb N^3$

A Detailed explanation for Archimedes area of parabolic segment by exhaustion proof ? Needed

why $\frac{f_n}{f_kf_{n-k}}$ is an integer for this sequence