fuck I ' m so tolerant <| sep |> Another one that comes to mind are the number of regular polyhedra I think they ' re called polytopes in higher dimensions . In 2 d , you obviously get infinite regular polygons . In 3 d , you get the 5 platonic solids . There are 6 in 4 d , but the rest of the dimensions only have 3 regular polytopes , and they ' re not very interesting either . The tetrahedron , cube , and octahedron all generalize to higher dimensions in a predictable manner . The 34 dimensional ones are the only interesting ones IMO . They are full of interesting symmetries . This video has a nice explanation of what they are 2 s 4 TqVAbfz 4 Sort of related , you can find a general solution to find the roots of degree 2 , 3 , 4 polynomials , and express them in terms of radicals . However , once you get to 5 dimensions , the symmetry group is too big to do so . My point is more that 4 d is also somewhat special .