<p>Generate the Fibonacci sequence in the fewest amount of characters possible. Any language is OK, except for one that you define with one operator, <code>f</code>, which prints the Fibonacci numbers.</p>

<p>Starting point: <strong><s>25</s> 14 characters</strong> in <strong>Haskell</strong>:</p>

<p><s>  <code>f=0:1:zipWith(+)f(tail f)</code> </s></p>

<pre><code>f=0:scanl(+)1f
</code></pre>

22 characters with dc:
```
```
1[pdd5**v1++2/lxx]dsxx
```
```
Invoke with either:
```
dc -e'1[pdd5**v1++2/lxx]dsxx'
```
Or:
```
echo '1[pdd5**v1++2/lxx]dsxx' | dc
```
Note: not my work, poached from
perlmonks
.