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Creating a random combination 
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#1
Dec312, 02:10 PM

P: 5

I am creating a random combination(code) for a client. I need to see what the total number of combinations there can be.
Please let me know if I am using the wrong word Combination vs Permutations. Formula: 2 letters + 2 numbers + 2 letters example: TR12FR The random letters are taken from 24 values: ABCDEFGHJKLMNPQRSTUVWXYZ The random Numbers are taken from 8 Values: 23456789 Any help would be greatly appreciated. Thanks Ryan. 


#2
Dec312, 02:18 PM

P: 2,939

combination is right you're selecting letters, numbers and more letters:
Choices for each character of your 6 charcter code: 24 * 24 * 8 * 8 * 24 * 24 = total number of codes possible Now if these could be rearranged then you'd have to worry about permutations to elimnate repeats in your counts. 


#3
Dec312, 02:22 PM

P: 5

Thank you 
So deduping these down to create 2.5 million unique codes using this formula will not be an issue, sense there are 21,233,664 possibilities. 


#4
Dec312, 02:39 PM

P: 2,939

Creating a random combination
okay what do you mean by deduping?



#5
Dec312, 02:46 PM

P: 5

Well sense this is just a random generator out of excel the possibility of it creating a duplicate is there, so i will need to just remove dupes, or nth select down to 2.5 million unique codes.
Just needed to make sure that the 6 digit using that formula could create that many unique codes. 


#6
Dec312, 02:51 PM

PF Gold
P: 6,283

How would you create 100000 consecutive random numbers from 1 to 100 ? 


#7
Dec312, 03:02 PM

P: 2,939

this reminds of how new programmers used to construct a deck of randomly sorted cards.
generate a number from 051 check if its present in the crd deck array if so then generate another. The better approach is to generate a sorted sequence of cards into an array and then to randomly shuffle two cards by selecting two indexes at random and swapping the cards. 


#8
Dec312, 03:22 PM

P: 5




#9
Dec312, 03:23 PM

P: 5

Thanks for the help.



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