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lanskey
  • Member for 6 years, 1 month
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11 votes
1 answer
284 views

Baby Rudin 1.14 is essentially Thales's theorem?

8 votes
1 answer
782 views

Converse Lagrange's Theorem for abelian groups

6 votes
2 answers
444 views

Category of multisets

4 votes
1 answer
162 views

Finding ring homomorphisms $\mathbb{Z}\to\mathbb{Z}/n\mathbb{Z}$

4 votes
1 answer
550 views

Is surjection an epimorphism without the axiom of choice?

3 votes
0 answers
272 views

Why is $0$ a zero divisor?

3 votes
0 answers
103 views

Proof check. Standard form for alternating polynomials

2 votes
1 answer
153 views

Show that $G$ is isomorphic to $\operatorname{Aut}_{G-Set}(G)$

2 votes
0 answers
59 views

Compact manifold without boundary is boundary of another manifold [duplicate]

2 votes
1 answer
102 views

Contraction map, inequality

1 vote
1 answer
30 views

If $B\triangleleft A\subset G,H\triangleleft G$ and $A/B$ abelian, then $(A\cap H )/(B\cap H)$ is abelian

1 vote
1 answer
687 views

Closure of interior of a convex closed set with nonempty interior is the set itself.

1 vote
1 answer
150 views

Inversion mapping four points to vertices of a parallelogram.

1 vote
1 answer
53 views

What are the essentials about classes

1 vote
0 answers
67 views

Integral over an ellipsoid of $z^2\mathrm{d}x\wedge\mathrm{d}y$, Stokes' theorem

1 vote
1 answer
413 views

Nowhere vanishing vector field on Moebius strip

1 vote
0 answers
35 views

$\lim\limits_{n\to\infty} n^a x_n$ [duplicate]

1 vote
1 answer
51 views

Is the Lie algebra so(2,6) semi-simple?

0 votes
1 answer
460 views

$\mathbb{Q}(\sqrt d)$ is the smallest subfield of $\mathbb{C}$ containing $\mathbb{Q}$ and $\sqrt d$ using field norm

0 votes
1 answer
95 views

continuous function on a circle without holomorphic continuation to the interior

0 votes
1 answer
209 views

Integral of a 2-form over an ellipsoid.