sum of unit roots is also unit root
110416
Sums of roots of unity
18814
Sum of the series $1+\frac{1\cdot 3}{6}+\frac{1\cdot3\cdot5}{6\cdot8}+\cdots$
1519
Sum of derivatives of a polynomial
26908
Partial Sums of Geometric Series
74058
Sums and products of algebraic numbers
145322
Sum of a Hyper-geometric series. (NBHM 2011)
62792
Can sum of a rational number and its reciprocal be an integer?
25125
Sum over multiple indices
83733
sum of polynoms of given property
127047
How to show that $\sum_{i=1}^n | \langle f, f_i\rangle |^2 \leq \Vert f \Vert^2$
69045
Solving this summation: $\sum_{i=1}^k i\cdot2^i$
48977
Polynomials having as roots the sum (respectively, the product) of two algebraic elements
70041
Sum with parameter convergence
68915
What are the units in $\mathbb{Z}[\root 3 \of 2]$?
22563
Units and Nilpotents
127169
Show that the zeros of $\sum_{k=1}^n kz^{k-1}$ are inside the unit disc
133076
Prove this sum equal to an expression.