Euler's totient function
Función φ de Euler
- Date
- 1763 · confidence high
- Place
- Berlin, Prussia (present-day Germany)
- Credited to
- Leonhard Euler
- Field
- Knowledge & symbols
What was discovered
Euler introduced this function, which counts the integers up to n that are coprime with n, in an 1763 paper on number theory. It became a central piece of modular arithmetic and, two centuries later, the mathematical basis of RSA encryption.
In 1763 Euler worked at the Berlin Academy (he did not return to Saint Petersburg until 1766); some sources place him in Russia by mistake.
What it led to
- RSA encryption
- Gauss's work on constructible polygons
- Development of group theory and abstract algebra
Built on
- Classical number theory and divisibility