Modular form
ANALYTIC FUNCTION ON THE UPPER HALF-PLANE WITH A CERTAIN BEHAVIOR UNDER THE MODULAR GROUP
Modular forms; Elliptic modular form; Modular function; Level of a modular form; Weight of a modular form; Nebentypus character; Nebentype character; Q-expansion; Modular form and modular function; Modular function and modular form
In mathematics, a modular form is a (complex) analytic function on the upper half-plane satisfying a certain kind of functional equation with respect to the group action of the modular group, and also satisfying a growth condition. The theory of modular forms therefore belongs to complex analysis but the main importance of the theory has traditionally been in its connections with number theory.