1

```
# Fibonacci number series
# tested with Python24 vegaseat 18oct2005
def fibonacci():
"""a generator for Fibonacci numbers, goes to next number in series on each call"""
a, b = 0, 1
while True:
yield a
a, b = b, a + b
f = fibonacci()
for x in range(13):
print f.next(), # 0 1 1 2 3 5 8 13 21 34 55 89 144
print
def fibo(n):
"""
use recursion to get Fibonacci numbers, returns the Fibonacci value for n
not very efficient because of the many function calls
"""
if n < 2:
return n
else:
return fibo(n - 1) + fibo(n - 2)
for x in range(13):
print "fibo(%d) = %d" % (x, fibo(x))
print
print "Calculating ..."
print
print "fibo(%d) = %d" % (30, fibo(30)) # this takes a moment!
```

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