Why is $\Bbb{Z}_2 \times A_5$ not solvable?
139218
Is this group solvable?
129750
Order of $SL_2(\mathbb{Z}/ n\mathbb{Z})$
115876
$D_6 \cong D_3\times \mathbb Z_2$
156909
$\Bbb{Z}_{26} \rtimes_{\alpha} \Bbb{Z}_{5} \cong \Bbb{Z}_{26} \times \Bbb{Z}_{5}$ as groups.
24351
The ring $\Bbb Z\left [\frac{-1+\sqrt{-19}}{2}\right ]$ is not a Euclidean domain
112933
Show that $Z\times Z$ is not cyclic...
87238
$(1 2)(3 4)$ does not commute with any nonidentity element of odd order in $A_5$.
78263
Prove $GL_n(\Bbb{R})/SL_n(\Bbb{R}) \cong \Bbb{R}^\times$
34252
$ z^n = a_n + b_ni $ Show that $ b_{n+2} - 2b_{n+1} + 5b_n = 0 $ (complex numbers)
109596
Isomorphism from $\mathrm{Aut}(\mathbb{Z}/2\mathbb{Z}\times \mathbb{Z}/2\mathbb{Z})$ to $S_3$
89215
How to describe the quotient group $\mathbb{Z} \times \mathbb{Z} / \langle (1, 2) \rangle$
144802
Prove no solution to $x^2\equiv3\bmod5$
137029
Prove that $\operatorname{Hom}_{\Bbb{Z}}(\Bbb{Q},\Bbb{Z}) = 0$ and show that $\Bbb{Q}$ is not a projective $\Bbb{Z}$-module.
153664
When is $\Bbb{Z[\zeta_n]}$ a PID?
41069
Justifying $\,\Bbb{Z}[i]/\langle 2\rangle\cong \Bbb{Z}[X]/\langle X^2+1,2\rangle\cong \Bbb{F}_2[X]/\langle X^2+1\rangle$
128732
$\mathbb Z_{p^n}$ is not the direct product of any family of its proper subgroups
4156
What is $\Bbb R^{\times}$? [unit group, ring to "times" power]