bang 

In left inlet: Sends out a previously unchosen random number from 0 to one less than the specified maximum limit. 
int 
randomgeneratorlimit [int]

In right inlet: Clears the list of already chosen numbers, and specifies the number of possible values for the random number generator. The random numbers will range from 0 to one less than this maximum limit. 
(inlet1) 
randomgeneratorlimit [int]

In right inlet: Clears the list of already chosen numbers, and specifies the number of possible values for the random number generator. The random numbers will range from 0 to one less than this maximum limit. 
clear 

In left inlet: Clears the list of already chosen numbers. 
seed 
randomgeneratorseed [int]

In left inlet: The word seed, followed by a number, provides a "seed" value for the random generator, which causes a specific (reproducible) sequence of pseudorandom numbers to occur. The number 0 uses the time elapsed since system startup (an unpredictable value) as the seed, ensuring an unpredictable sequence of numbers. This unpredictable seed is used by default when the urn object is created. However, once all numbers have been chosen, the sequence will repeat. Therefore, in order to achieve a nonrepeating sequence of numbers, you will need to send the urn object the seed 0 message each time you send it the clear message. 