as listed above the question is how many and which three digit NIP can be formed whit the use of prime numbers[/B]
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"
i dont know if i am right can you help me?