How Many Permutations Are There of the Digits in the String

question 13

Essay

How many permutations are there of the digits in the string 12345 that leave 3 fixed but leave no other integer fixed? (For instance, 24351 is such a permutation.)

---

Definitions:

Message Pane

The section of an email or messaging application where the contents of selected or active messages are displayed for reading or editing.

RSS

A type of web feed that allows users to access updates to online content in a standardized, computer-readable format.

Email Signature

A block of text automatically appended at the end of an email message that often contains the sender's name, contact information, and sometimes a quote or a company’s logo.

Email Provider

A service or company that offers email services, facilitating sending, receiving, and managing electronic mail messages.