Exponentiation
Exponentiation is a mathematical operation, written as , involving two numbers, the "base" and the "exponent" . When is a positive integer, exponentiation corresponds to repeated multiplication of the base: that is, is the product of multiplying bases:
Surreal number
A general exponentiation can be defined as , giving an interpretation to expressions like . Again it is essential to distinguish this definition from the "powers of ω" function, especially if ω may occur as the base.