Abstract
The Schröter formula is an important theta function identity. In this paper, we will point out that some well-known addition formulas for theta functions are special cases of the Schröter formula. We further show that the Hirschhorn septuple product identity can also be derived from this formula. In addition, this formula allows us to derive four remarkable theta functions identities, two of them are extensions of two well-known Ramanujan's identities related to the modular equations of degree 5. A trigonometric identity is also proved.
| Original language | English |
|---|---|
| Pages (from-to) | 1477-1488 |
| Number of pages | 12 |
| Journal | International Journal of Number Theory |
| Volume | 5 |
| Issue number | 8 |
| DOIs | |
| State | Published - Dec 2009 |
Keywords
- Addition formula
- Elliptic function
- Modular equation
- Rogers-Ramanujan's continued fraction
- Schröter formula
- Septuple product identity
- Theta function