# Thread: help me in Mathematica

1. ## help me in Mathematica

how to find that summation by Mathematica Wolfram

$\sum_{x\in A} \sin(\pi x)$

$A={{1,\frac{1}{2},\frac{1}{3},\frac{1}{4},........ .}}$

2. Originally Posted by nice rose
how to find that summation by Mathematica Wolfram

$\sum_{x\in A} \sin(\pi x)$

$A={{1,\frac{1}{2},\frac{1}{3},\frac{1}{4},........ .}}$
Input: Sum[Sin[Pi/n], {n, 1, Infinity}].

Message: Sum::div: Sum does not converge.

3. Originally Posted by nice rose
how to find that summation by Mathematica Wolfram

$\sum_{x\in A} \sin(\pi x)$

$A={{1,\frac{1}{2},\frac{1}{3},\frac{1}{4},........ .}}$

Since for small $u$ we have $\sin(u)\approx u$ this is obviously not convergent as the tail of the sum behaves like the harmonic series which is known to be divergent.
.

CB