Recursion

Recursion occurs when a thing is defined in terms of itself or of its type. Recursion is used in a variety of disciplines ranging from linguistics to logic. The most common application of recursion is in mathematics and computer science, where a function being defined is applied within its own definition. While this apparently defines an infinite number of instances (function values), it is often done in such a way that no loop or infinite chain of references can occur.

In mathematics and computer science, a class of objects or methods exhibit recursive behavior when they can be defined by two properties:

For example, the following is a recursive definition of a person's ancestors:

The Fibonacci sequence is a classic example of recursion:

${\displaystyle {\text{Fib}}(0)=0{\text{ as base case 1,}}}$

${\displaystyle {\text{Fib}}(1)=1{\text{ as base case 2,}}}$

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