Looking for a proof: ! n = [n!/e]

For students of class 11-12 (age 16+)
Rabeeb
Posts: 25
Joined: Tue Dec 14, 2010 7:52 pm
Location: Mymensingh, Bangladesh
Contact:

Looking for a proof: ! n = [n!/e]

Unread post by Rabeeb » Wed Feb 04, 2015 4:40 pm

Can any1 plz give an ezly understandable proof of how " !n = [n!/e] "?
(Here !n denotes the derangement of n elements and [x] denoted the closest integer to x)

User avatar
*Mahi*
Posts: 1175
Joined: Wed Dec 29, 2010 12:46 pm
Location: 23.786228,90.354974
Contact:

Re: Looking for a proof: ! n = [n!/e]

Unread post by *Mahi* » Wed Feb 04, 2015 11:14 pm

Rabeeb wrote:Can any1 plz give an ezly understandable proof of how " !n = [n!/e] "?
(Here !n denotes the derangement of n elements and [x] denoted the closest integer to x)
Please do not use incorrect English intentionally. That creates a very poor impression of you while lowering the IQ of the whole forum by 5 points.

For your question -
Image
Use this formula to approximate $!n$.
Please read Forum Guide and Rules before you post.

Use $L^AT_EX$, It makes our work a lot easier!

Nur Muhammad Shafiullah | Mahi

Post Reply