SQL Functions - factorial

Question

I am a beginner in SQL Functions. What is the best way to create a function for factorial in SQL Server- Say 10!

Answer 1

/* Print Factorial Sequence*/

WITH MYCTE AS(
 SELECT VAL=1,NUM =1 
 UNION ALL
 SELECT VAL=VAL*(NUM+1),NUM = (NUM +1)
 FROM MYCTE
 WHERE NUM < 11
)                  
SELECT VAL FROM MYCTE
 OPTION (MAXRECURSION 0);