TypeError when simplifying factorial ratio

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TypeError when simplifying factorial ratio #21307

Open arminstraub opened 7 years ago

arminstraub commented 7 years ago

Trying to simplify symbolic expressions, I just ran into the following issue (naturally, this is simplified from what I was working with):

sage: ((2^x)^2/((2^(x+1))^2*binomial(2*x,x))).full_simplify()
...
TypeError: ECL says: In function CAR, the value of the first argument is
  -2
which is not of the expected type LIST

Component: symbolics

Issue created by migration from https://trac.sagemath.org/ticket/21307

arminstraub commented 7 years ago

comment:1

I was trying to trace the issue and think that things go wrong in Maxima's factcomb. A minimal example of sorts is:

sage: maxima_calculus("factcomb(2^(2*x-2*(x+1))*factorial(x))")

If that is indeed the source of the trouble, it should probably be reported upstream. Sage v7.3 comes with Maxima v5.35.1. Can someone with access to the newest version of Maxima (at least 5.38.1) quickly check if this issue still exists?