[GSoC] Series: Fixes RecursionError and Timeout in limit evaluations

[sachin-4099]

Fixes: #8208
Fixes: #14514
Fixes: #15202
Fixes: #15282
Fixes: #16714

Brief description of what is fixed or changed

Changes have been done in mrv() function of gruntz.py to handle the indeterminant form of 1**oo more accurately.

Some other changes have been done in Add._eval_as_leading_term() to handle cases in a better way, where leading term has to be evaluated using series computation.

Some major changes have been done in the cancel() function of polytools.py to speed up the algorithm.

Other Comments

Regression Tests have been added.

Release Notes

• series
  • Changes in mrv() function of gruntz.py and cancel() function of polytools.py resolves RecursionError and Timeout in limit evaluations

[sympy-bot]

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• series
  • Changes in mrv() function of gruntz.py and cancel() function of polytools.py resolves RecursionError and Timeout in limit evaluations (#19646 by @sachin-4099)

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Fixes: #8208
Fixes: #14514
Fixes: #15202
Fixes: #15282
Fixes: #16714

#### Brief description of what is fixed or changed

Changes have been done in `mrv()` function of `gruntz.py` to handle the indeterminant form of `1**oo` more accurately.

Some other changes have been done in `Add._eval_as_leading_term()` to handle cases in a better way, where `leading term` has to be evaluated using `series computation`.

Some major changes have been done in the `cancel()` function of `polytools.py` to speed up the algorithm.

#### Other Comments
Regression Tests have been added.


#### Release Notes


<!-- BEGIN RELEASE NOTES -->
* series
  * Changes in `mrv()` function of `gruntz.py` and `cancel()` function of `polytools.py` resolves `RecursionError` and `Timeout` in limit evaluations
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[codecov]

Codecov Report

Merging #19646 into master will increase coverage by 0.000%.
The diff coverage is 100.000%.

@@            Coverage Diff             @@
##            master    #19646    +/-   ##
==========================================
  Coverage   75.668%   75.668%            
==========================================
  Files          657       658     +1     
  Lines       170689    171250   +561     
  Branches     40262     40422   +160     
==========================================
+ Hits        129158    129583   +425     
- Misses       35872     35997   +125     
- Partials      5659      5670    +11     

[jksuom]

Thanks, I think that this is ready to go.

[oscarbenjamin]

Two regressions have recently emerged from this PR: #21024 and #21031