nC doc example in sympy live shows TypeError: 'Integer' object is not iterable

[snowch]

The first code block for nC shows an error:

Python console for SymPy 1.5.1 (Python 2.7.12)

These commands were executed:
>>> from __future__ import division
>>> from sympy import *
>>> x, y, z, t = symbols('x y z t')
>>> k, m, n = symbols('k m n', integer=True)
>>> f, g, h = symbols('f g h', cls=Function)

>>> from sympy.functions.combinatorial.numbers import nC
>>> from sympy.utilities.iterables import multiset_combinations
>>> nC(3, 2)
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/base/data/home/apps/s~sympy-live-hrd/66.426491309333028408/sympy/sympy/functions/combinatorial/numbers.py", line 1715, in nC
    return nC(_multiset_histogram(n), k, replacement)
  File "/base/data/home/apps/s~sympy-live-hrd/66.426491309333028408/sympy/sympy/functions/combinatorial/numbers.py", line 1435, in _multiset_histogram
    n = list(n)
TypeError: 'Integer' object is not iterable
>>> nC('abc', 2)
3

>>> nC('aab', 2)
2

Also the last code block errors too:

>>> sum(nC(4, i) for i in range(5))
Exception in SymPy Live of type 
<type 'exceptions.TypeError'>
for reference the last 5 stack trace entries are
Traceback (most recent call last):
  File "/base/data/home/apps/s~sympy-live-hrd/66.426491309333028408/app/handlers.py", line 271, in post
    live.evaluate(statement, session, printer, stream)
  File "/base/data/home/apps/s~sympy-live-hrd/66.426491309333028408/app/shell.py", line 280, in evaluate
    exec code in statement_module.__dict__
  File "<string>", line 1, in <module>
TypeError: 'NoneType' object is not iterable

[oscarbenjamin]

This is because sympy-live is running an older version of sympy: sympy/sympy-live#175

SymPy master gives:

In [1]: from sympy.functions.combinatorial.numbers import nC

In [2]: nC(3, 2)
Out[2]: 3

In [3]: sum(nC(4, i) for i in range(5))
Out[3]: 16