can sympy do this

[Martin Chan]

since out of memory, 

i hope sympy can do this, but i can not find this function

http://www.mapleprimes.com/questions/202338-Error-in-Combinatpermute-Maple

how to do the same as in above link,  my post

[Aaron Meurer]

SymPy can make use of Python's generators, which compute things like
this one at a time, rather than all at once (which would indeed fill
all your memory). For instance in the Python standard library

from itertools import permutations

computes permutations as a generator.

Of course, any computation you do will still need to not store every
permutation in memory, which will necessarily use more memory than you
have due to the large number of combinations.

Aaron Meurer

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[Christophe Bal]

Hello.

There is n! permutations of a set of n elements and n! ~ sqrt(2 pi n) (n/e)^n due to the Stirling's approximation. So you can expect to have all the permuations with not small value of n.

Christophe BAL

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