Bounds on the frequencies of a vibrating membrane, provided its shape can tile the plane.

You can find three primitive Pythagorean triangles with the same area, but what about four?

Given three mutually tangent circles, there is an elegant theorem for finding two more circles tangent to all three.

Several elliptic curves which Zcash uses in zero knowledge proofs are named after characters from Lewis Carroll: Jubjub, Bandersnatch, Tweddledee, Tweedledum

Two elliptic curves used in Zcash for zero-knowledge proofs, one named after a Greek goddess of war and one after a Roman goddess of home and hearth

Cycles of ellptic curves have the property that the number of points on one curve equals the field size of the next curve.