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## Homework Statement

as listed above the question is how many and which three digit NIP can be formed whit the use of prime numbers[/B]

## Homework Equations

nothing currently trying to understand[/B]

## The Attempt at a Solution

well i have found at least 168 primer numbers below 1000 i mean in the range of three digit,

and grouped in three groups:

numbers of 1 digit "4"

numbers of two digit "21"

numbers of three digit ""143"

as far i know this is a permutation because order matters so 717 is diferent of 177 and 771 so

i am thinking of like a billion of ways to put those numbers to form a NIP, my question is this is even doable?

how can i start to mix this to make to the final count of how many ways one can put all those numbers to form the NIPS

***** update: i think for the three digit numbers there is a rule of 3! on each one so making 6 ways to put that number so if i multiply that for 143 this gives me 858 ways in total but i dont know if this is correct, and its just for the three digit numbers

**** second update:

i permuted every 1 digit number whit every 2 digit number

11 and 2,3,5,7 ok then 112, 211,121. so 3!=6 then 6*4 the 4 represent the 1 digit numbers

24 is the total acoding to this so 24*21 21 represents the total 2 digit numbers, this gives to me

504 but previously i ve calculated the permutation of 3 digit numbers so using the prefix "and"

504*858=432432

i dont know if i am right can you help me?

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