A problem of Number Theory
35326
There are infinitely many $N$ such that $\frac{N}{2}$ is a perfect square, $\frac{N}{3}$ is a perfect cube, and $\frac{N}{5}$ is a perfect fifth power
140632
A problem on Binomial Theorem
33495
A limit problem about $a_{n+1}=a_n+\frac{n}{a_n}$
106271
Solutions of Diophantine equations in Natural numbers
130636
A result of Erdős on increasing multiplicative functions
87267
Conjecture similar to Fermat's Theorem.
144571
A conjecture including binomial coefficients
90081
problems in group theory
41571
Prove that in a sequence of numbers $49 , 4489 , 444889 , 44448889\ldots$
6700
An Olympiad problem in prime numbers :can we proof that "n" is prime in this case "
41412
Inequality in number theory
158124
Sum of all the positive integers problem
45460
Proof verification of a number theory problem involving sequences.
157717
What is a mathematical solution to this problem? (Project Euler #106)
48692
A problem about the graph theory
91105
For every $n\ge3$ there exists $n$ different integers $a_1,...,a_n$ so that $\frac{1}{a_1}+\frac{1}{a_2}+...+\frac{1}{a_n}=1$
157711
Number Theory: Prove that $m | \phi(a^m - 1)$