Into how many finite regions does $n$ lines in general position divide the plane?
16582
Show that $n$ lines separate the plane into $\frac{n^2+n+2}{2}$ regions
114795
Closed form for the area of a convex cyclic n-gon, given the set of edge lengths
24477
Monochromatic squares in a colored plane
43845
Partitioning the edges of $K_n$ into $\lfloor \frac n6 \rfloor$ planar subgraphs
62175
A general formula for $n$ distinguishable arrangements of length $\ell$ of a sequence of a given size?
6432
How many ways can N elements be partitioned into subsets of size K?
132133
Number of elements of a finite field
129002
Number of triangles formed by $m$ lines
10910
How many edges does an undirected tree with $n$ nodes have?
90184
Partition of circumference into $3k$ arcs
42945
Find the minimal number of guard points of polygon
126885
canonical representation of three skew lines in $\mathbb{P}^3$
78422
Calculate the number $o(\mathbb{R})$ of open subsets of the real line.
22540
Bisecting line segments in a tetrahedron.
119681
How to show whether 3 planes have a common line of intersection
109740
Bresenham's line algorithm
132085
Minkowski sum and product of 2D-regions