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 | 1 | initial version |
The reason is that Sage considers that Ds still has one variable, though it is a dummy one:
sage: Ds
t5040*sum((-1)^l/factorial(l), l, 0, 7)
sage: Ds.variables()
(l,)
You can solve this issue by simplifying the expression:
sage: Ds.simplify_full()
1854
| | 2 | No.2 Revision |
The reason is that Sage considers that Ds still has one variable, though it is a dummy one:
sage: Ds
t5040*sum((-1)^l/factorial(l), l, 0, 7)
sage: Ds.variables()
(l,)
You can solve this issue by simplifying the expression:
sage: Ds.simplify_full()
1854
By the way, please note that the lines:
D=function('D')(n,l)
Dn=function('Dn')(n,l)
are useless, since D and Dn are overwritten just after.
