Prove that there exists a one-color $K_3$ in a $K_{17}$ which is colored with three colors
52056
Chromatic Triangles on a $K_{17}$ graph
94958
Prob. 6 (d), Chap. 1, in Baby Rudin, 3rd ed: How to complete this proof?
61340
Prove that there exists bipartite graph with this degree sequence: $(3,3,3,3,3,5,6,6,6,6,6,6,6,6)$
141265
Finding a normal and not normal subgroup of $S_3$
23239
Prove that the following map has at least $k-2$ fixed points
37331
Prove that every set with more than one element has a permutation without fixed points
136083
Show that $\sigma\circ\phi : G_1 \to G_3$ is an isomorphism
110760
Chromatic Polynomial
105405
Product of three consecutive positive integers is never a perfect power
48127
Are there infinitely many $A\in \mathbb{C}^{2 \times 2}$ satisfying $A^3 = A$?
133017
Prove that $n^n>1\times3\times5\times7\times \dots\times(2n-1)$
31347
$A_n$ is generated by 3-cycles given $n\geq 3$. Is this proof correct?
83747
$2$ out of $3$ property of the unitary group
34424
Determining ring of integers for $\mathbb{Q}[\sqrt{17}]$
140359
Can the sum of finitely many inverses of distinct odd integers $\geq 3$ be 1?
61546
Prove that for each prime $p$ there exists a nonabelian group of order $p^3$
116175
Show that $\gcd(3k+2,5k+3)=1$