擅长:python、mysql、java
<pre><code>def somefunc(n):
if not n:
return [1]
else:
return list(itertools.chain.from_iterable([(i+1, 3*i) for i in somefunc(n-1)]))
</code></pre>
<p>输出:</p>
<pre><code>In [20]: somefunc(3)
Out[20]: [4, 9, 7, 18, 5, 12, 10, 27]
In [21]: somefunc(2)
Out[21]: [3, 6, 4, 9]
In [22]: somefunc(1)
Out[22]: [2, 3]
</code></pre>