Beispiel: Fibonacci-Zahlen
#!/usr/bin/python
 
def fib(n):
  if n<2: return n
  return fib(n-1)+fib(n-2)
 
print fib(30)
#!/usr/bin/perl
 
sub fib {
  if ($_[0]<2) {return $_[0];}
  return &fib($_[0]-1)+&fib($_[0]-2);
}
 
print &fib(30),"\n";
#include <stdio.h>
 
int fib(int n)
{
  if (n<2) return n;
  return fib(n-1)+fib(n-2);
}
 
main()
{
  printf("%d\n", fib(30));
}
 		#!/usr/bin/tclsh
 
proc fib {n} {
  if {$n < 2} {return $n}
  return [expr [fib [expr $n-1]]+[fib [expr $n-2]]]
}
 
puts [fib 30]