The symbol for pi is the 16th letter of the Greek alphabet. Many Greek letters are used in mathematics for various functions.
Pi is approximately equal to 3.141592652389793238462.
Pi as a mathematical symbol was introduced by William Jones in 1706
Pi.
It was the mathematician William Jones who first used pi as a mathematical symbol in 1706
Pi as a mathematical symbol was introduced by William Jones in 1706
Mathematician Rudolph Swetchefriz{Added} The symbol is not "for" pi but is pi - one of the letters of the Greek alphabet.
Pi was first used as a mathematical symbol by the mathematician William Jones in 1706.
Maurits Escher was a remarkable Swiss mathematician and teacher that was responsible for instituting the use of the symbol pi in mathematical notation.
Euler
The symbol you are referring to is likely the "caret" symbol, which is commonly used to indicate exponentiation in mathematical expressions. It is not a standard mathematical notation for representing the number Pi.
Actually, the number was discovered and then a symbol had to be assigned to it. Letters of the Greek alphabet are traditionally used for mathematical things, to the symbol for pi was naturally chosen from the Greek alphabet.
pi is represented by the Greek letter (of the same name) π and is the ratio of the circumference of a circle to its diameter.