Formulas
- Hilbert–Schmidt operator
- Equivalence of categories
- Equivalence of metrics
- Hilbert–Smith conjecture
- Hill differential equation
- Hill tetrahedron
- Equivariant cohomology
- Hirzebruch signature theorem
- Hirzebruch–Riemann–Roch theorem
- Equivariant map
- Equivariant topology
- History monoid
- Erdős cardinal
- Erdős space
- Erdős–Diophantine graph