Prove that every edge-coloring of $K_{17}$ with $3$ colors contains a monochromatic $K_3$.
1000
$K_6$ contains at least two monochromatic $K_3$ graphs.
62996
A problem regarding the proof of ${p^nk\choose p^n}\equiv k\mod p$, where $p\nmid k$.
77579
Proof by induction that $ 169 \mid 3^{3n+3}-26n-27$
104903
Lower bound for Ramsey numbers: $R( n + 2 , 3 )>3n$
124467
Can $(X_1,X_2) \cap (X_3,X_4)$ be generated with two elements from $k[X_1,X_2,X_3,X_4]$?
35666
How to prove the divisibility rule for $3\, $ [casting out threes]
55944
Chromatic polynomial of connected graph $ \leq x(x-1)^{n-1}$
9847
Prove that if every node in a simple graph $G$ has degree $3$ or higher, then $G$ contains a cycle with a chord.
46550
Proving an 'obvious' Ramsey upperbound
14932
What would be the number of inequivalent $6$-colourings of the faces of a cube?
122330
Prove that there exists some $c\in(-3,3)$ such that$ \ \ g(c) \cdot g''(c)<0$.
23097
Prove that every number ending in a $3$ has a multiple which consists only of ones.
139657
Prove that if $\chi(G-u-v)=\chi(G)-2$ for every vertices $u, v$ ($u \ne v$) then G is complete graph.
105425
The intervals $(2,4)$ and $(-1,17)$ have the same cardinality
142534
Proof of $k {n\choose k} = n {n-1 \choose k-1}$ using direct proof
155090
A graph whose every odd cycle is a triangle is 4-colorable
142917
Graph vertex chromatic number in a union of 2 sub-graphs