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drummers-lowrise
1) Message boards : General discussion : Puzzle Of The Week (Message 95567)
Posted 1571 days ago by Profile steveking
211 is prime.


Argh... prime and greater than the largest of the multiplicative inverse pair. Think Cryptography.
2) Message boards : General discussion : Puzzle Of The Week (Message 95552)
Posted 1571 days ago by Profile steveking
In Z (the integers) we have:

1091*1647 = 1796877


So if n is the unknown modulus we seek, then:

1796877 == 1 (mod n)


This means that n can be any divisor of 1796877-1. We factorize:

1796876 = 2^2 * 211 * 2129


So we have the solutions:

n = 1, 2, 4, 211, 422, 844, 2129, 4258, 8516, 449219, 898438, 1796876.


If we require n to exceed 1647, then the solutions are 2129, 4258, 8516, 449219, 898438, 1796876. And if we required that and further that n is a prime, the only solution is 2129. However, as stated in the original post, all twelve n above are solutions.

/JeppeSN



My apology, I should have stated or implied that the answer must be Prime.
3) Message boards : General discussion : Puzzle Of The Week (Message 95511)
Posted 1572 days ago by Profile steveking
211


211 is incorrect

Maybe we should make it Problem Of The Month.


1091 = 36 (mod 211)
1647 = 170 (mod 211)
36 * 170 = 1 (mod 211)

2129 does it too.



2129 is the only correct answer.
4) Message boards : General discussion : Puzzle Of The Week (Message 95499)
Posted 1573 days ago by Profile steveking
211


211 is incorrect

Maybe we should make it Problem Of The Month.



Hint: the base or modulo must be greater than the larger of the two multiplicative inverses.
5) Message boards : General discussion : Puzzle Of The Week (Message 95498)
Posted 1573 days ago by Profile steveking
211


211 is incorrect

Maybe we should make it Problem Of The Month.
6) Message boards : General discussion : Puzzle Of The Week (Message 95493)
Posted 1573 days ago by Profile steveking
Can you start a Puzzle or Problem Of The Week. Something from the range of High School to 1st year Grad level?

I'll start.

You are walking on a beach and you encounter a Genie. He says: If you can answer this question I will let you pass. Q: 1091 and 1647 are multiplicative inverses of each other in what base or modulo?

7) Message boards : Proth Prime Search : Completed But Waiting Validation (Message 95478)
Posted 1573 days ago by Profile steveking
Each WU needs at least 2 different people to return a result for it to validate. When your task is showing as "Pending Validation", it just means that you've returned your result to the server already, but the other person assigned the job (usually called wingman) didn't finished processing yet. It may or may not be prime, but it isn't 99.99% of the time.

Just wait a few days and it should validate. Things take a while to validate sometimes. For example, this guy has been waiting ever since Jan to have it's WU validated!



I believe if a WU has not been validated by the first wingman in N number of hours... then it should be assigned to a second wingman to get the project moving. Any thoughts on this idea?
8) Message boards : Proth Prime Search : Completed But Waiting Validation (Message 95473)
Posted 1574 days ago by Profile steveking
Today is June 3rd and yet I still have a work unit/task from June 1 that is still waiting for validation. Could this mean a Prime was found but it is waiting for the result to be validated?
9) Message boards : General discussion : Distribution of digits 0-9 that make up Primes (Message 95429)
Posted 1576 days ago by Profile steveking
Has anyone analyzed the digits that make up large primes and create a histogram of the occurrence of each digit? Are they evenly distributed or do some digits occur more than others... across all large primes?
10) Message boards : Proth Prime Search : How can we beat GIMPS (Message 95427)
Posted 1576 days ago by Profile steveking
I'm good. I'll stay with Proth.


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