Find the number of one-one functions from a finite set A to A ,where n(A) = p
Refer the link to answer similar to your query:
https://www.meritnation.com/ask-answer/question/find-the-number-of-all-one-one-functions-from-set-a-1-2-3/relations-and-functions/7265157
https://www.meritnation.com/ask-answer/question/find-the-number-of-all-one-one-functions-from-set-a-1-2-3/relations-and-functions/7265157