[Merged by Bors] - feat(FaaDiBruno): add estimates on the difference between taylor series

[urkud]

Prove an estimate on (f ∘ g)^{(n)} that can be used to show, e.g., that the composition of two C^{n+(α)} functions is a C^{n+(α)} function.

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[github-actions]

PR summary f141b457d6

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ Nat.exists_lt_iff_fin
+ Nat.forall_lt_iff_fin
+ norm_compAlongOrderedFinpartitionL_apply_le
+ norm_compAlongOrderedFinpartition_sub_compAlongOrderedFinpartition_le
+ taylorComp_sub_taylorComp_isBigO
+ taylorComp_sub_taylorComp_isLittleO

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for script/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[sgouezel]

bors d+

[sgouezel]

This one would deserve a docstring.

[sgouezel]

ditto

[mathlib-bors]

✌️ urkud can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[leanprover-community-mathlib4-bot]

As this PR is labelled auto-merge-after-CI, we are now sending it to bors:

bors merge

[mathlib-bors]

Canceled.

[leanprover-community-mathlib4-bot]

As this PR is labelled auto-merge-after-CI, we are now sending it to bors:

bors merge

[mathlib-bors]

Pull request successfully merged into master.

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