Fibonacci series recursion error

[Jason Friedman]

> import os
> def fib(n):
>        if n == 1:
>          return(n)
>        else:
>          return (fib(n-1)+fib(n-2))
>
> list=fib(20)
> print(list)
>
> The above function return the
> return (fib(n-1)+fib(n-2))
>
>
> RuntimeError: maximum recursion depth exceeded in comparison
> [36355 refs]
>
> can any one help

The first call to fib() recursively calls fib() twice.  Each of those
will call fib() twice.  Each of those will call fib() twice.  Pretty
soon, you've got a lot of calls.

Have a look at:  http://en.literateprograms.org/Fibonacci_numbers_(Python).