stirling
所属分类:lean
开发工具:Lean
文件大小:0KB
下载次数:0
上传日期:2022-06-17 11:54:28
上 传 者:
sh-1993
说明: 斯特林公式在Lean中的证明,
(A proof of Stirling s formula in Lean,)
文件列表:
LICENSE (11357, 2022-06-17)
leanpkg.toml (241, 2022-06-17)
src/ (0, 2022-06-17)
src/90_stirlings_formula.lean (33904, 2022-06-17)
# A proof of [Stirling's formula](https://en.wikipedia.org/wiki/Stirling%27s_approximation) in [Lean](https://leanprover.github.io/)
We provide a proof of Stirling's formula in the following form:
$$n! \sim \sqrt{2\pi n}\left(\frac{n}{e}\right)^n.$$
More concretely, we define
```lean
noncomputable def an (n : ) : :=
(n.factorial : ) /
((real.sqrt(2*n)*((n/(exp 1)))^n))
```
and prove
```lean
lemma an_has_limit_sqrt_pi: tendsto
(λ (n : ), an n) at_top ( (sqrt π)) :=
```
We follow roughly [this proof](https://proofwiki.org/wiki/Stirling%27s_Formula).
Currently the proof is complete, but in very messy state.
We plan to clean and streamline the proof soon.
近期下载者:
相关文件:
收藏者: