Hartshorne exercise II.4.5(c)
99217
Hartshorne's Exercise II.4.5(c). A third time.
153306
Number of sigma algebras for set with 4 elements
90433
Isomorphisms between $(\mathbb Z_4,+)$ and $(U_5,*)$
18198
Lang Algebra Chapter 6 Theorem 9.4
125474
Exercise 16 from chapter 3 of Stein & Shakarchi's complex analysis
111348
Show that $\mathrm{S}_{m} \times \mathbb{N}^{m} \rightarrow \mathbb{N}^{m}$ defines an action of $\mathrm{S}_{m}$ on $\mathbb{N}^{m}$
61526
An exercise about nilpotent quotient groups
130993
4 Element abelian subgroup of S5.
144394
Order 2 elements in finite characteristic field
81221
The prime number theorem over a finite field - Lang's *Algebra*, Chapter V, Exercise 23(b)
57528
Hartshorne Theorem 8.17
118612
Neutral element in $\hom_C(A, B)$
147982
Exercise 1.10 from Silverman "The Arithmetic of Elliptic Curves "
96071
How to show that a prime ideal of height 2 can’t necessarily be generated by 2 elements? (Hartshorne exercise I.1.11)
156611
Hartshorne Problem 1.2.14 on Segre Embedding
42213
Computing $\text{Gal}(\mathbb{Q}^{ab}/\mathbb{Q})$
69945
A PDE exercise from Gilbarg Trudinger. problem 2.2