$x^2 + x + 41$ is composite
101882
Does this polynomial evaluate to prime number whenever $x$ is a natural number?
143510
Prove that $n=\frac{5^{125}-1}{5^{25}-1}$ is a composite number
23638
$a^2b^2+a^2c^2+b^2c^2\leq 3$
127390
Second derivative of a composite function
41069
Justifying $\,\Bbb{Z}[i]/\langle 2\rangle\cong \Bbb{Z}[X]/\langle X^2+1,2\rangle\cong \Bbb{F}_2[X]/\langle X^2+1\rangle$
143754
Finding the solution of the congruence $4x\equiv16\pmod{26}$
8504
Factoring $x^n + y^n$ over the integers
20486
Numbers representable as $x^2 + 2y^2$
27963
How many ways a composite number can be resolved into two factors which are prime to each other?
146887
Prove that $f=x^4-4x^2+16\in\mathbb{Q}$ is irreducible
147600
Calculating large Bell number modulo a composite number
103763
Minimal polynomial of $\sqrt{2}+\sqrt{3}$ over $\mathbb Q$
148713
If $p\geq 5$ is a prime number, show that $p^2+2$ is composite.
33177
All numbers of form $10^{k} + 1$ are composite for $k{\gt}2$ proof
148901
Can a composite number $n$ be the arithmetic mean of $\sigma(n)$ and $\varphi(n)$?
96237
$1^2 + 2^2 + 3^2 + \cdots + (n-1)^2 \equiv 0$ mod n iff $n \equiv \pm 1$ mod 6
105442
Show that any prime divisor of $x^4+x^3+x^2+x+1$, with $x\in\mathbb{N}$, is $5$ or $1$ mod $5$