title: History of the function concept
context: The term "function" was literally introduced by Gottfried Leibniz, in a 1673 letter, to describe a quantity related to points of a curve, such as a coordinate or curve's slope.[9] Johann Bernoulli started calling expressions made of a single variable "functions." In 1698, he agreed with Leibniz that any quantity formed "in an algebraic and transcendental manner" may be called a function of x.[10] By 1718, he came to regard as a function "any expression made up of a variable and some constants."[11] Alexis Claude Clairaut (in approximately 1734) and Leonhard Euler introduced the familiar notation      f ( x )    {\displaystyle {f(x)}}   for the value of a function.[12]
question: Who first introduced the concept of mathematical functions?
answers: Gottfried Leibniz