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Old 2021-02-22, 01:32   #1
murzyn0
 
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Minus infinite mersenne prime numbers

2^p - 1, where p is prime number is always prime number, for example:
2^7 - 1 is 127,
2^127 - 1 is 170141183460469231731687303715884105727,
2^170141183460469231731687303715884105727 - 1 is big number, but its prime number, so it's eveidnce that there is infinity mersenne prime numbers
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Old 2021-02-22, 01:52   #2
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https://primes.utm.edu/mersenne/index.html#unknown

Proving a ~10^51217599719369681875006054625051616349 digit number prime is beyond all known technolgy.

Last fiddled with by paulunderwood on 2021-02-22 at 01:54
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Old 2021-02-22, 01:56   #3
Batalov
 
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Quote:
Originally Posted by murzyn0 View Post
2^p - 1, where p is prime number is always prime number
Really?
So if p=11 is a prime number, then 2^11-1 "is always prime number"?
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Old 2021-02-22, 01:59   #4
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Old 2021-02-22, 11:20   #5
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Unfortunately you forgot to end with QED so the proof is inadmissible.
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Old 2021-02-22, 19:48   #6
murzyn0
 
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Quote:
Originally Posted by Batalov View Post
Really?
So if p=11 is a prime number, then 2^11-1 "is always prime number"?
My bad, p must be always result of mersenne prime numbers.
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Old 2021-02-22, 21:03   #7
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Quote:
Originally Posted by murzyn0 View Post
My bad, p must be always result of mersenne prime numbers.
2^13-1== 8191 is prime. 2^8191-1 is not. Easy to check.
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Old 2021-02-22, 21:33   #8
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Quote:
Originally Posted by paulunderwood View Post
2^13-1== 8191 is prime. 2^8191-1 is not. Easy to check.

but, 13 in 2^13-1 is not a mersenne prime numbers.

2^p - 1, where p is a mersenne prime, yields a different mersenne prime.
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Old 2021-02-22, 21:39   #9
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Quote:
Originally Posted by murzyn0 View Post
but, 13 in 2^13-1 is not a mersenne prime numbers.

2^p - 1, where p is a mersenne prime, yields a different mersenne prime.
But that's not proven. And no, 3 examples are not proof.
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Old 2021-02-22, 21:52   #10
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MODERATOR NOTE: Thread closed.
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Old 2021-02-23, 03:19   #11
retina
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Quote:
Originally Posted by murzyn0 View Post
2^p - 1, where p is prime number is always prime number, for example:
2^7 - 1 is 127,
2^127 - 1 is 170141183460469231731687303715884105727,
2^170141183460469231731687303715884105727 - 1 is big number, but its prime number, so it's eveidnce that there is infinity mersenne prime numbers
Eveidnce [sic] != proof.
Quote:
Originally Posted by murzyn0 View Post
but, 13 in 2^13-1 is not a mersenne prime numbers.

2^p - 1, where p is a mersenne prime, yields a different mersenne prime.
2^5-1 (=31) is prime. 2^31-1 is prime. But 2^(2^31-1)-1 is composite, factors are known.

How back to you go? Because 5 is not a Mersenne prime. And your example above, 2 is not a Mersenne prime either, so the sequence 2, 3, 7, 127, ... doesn't start with a Mersenne prime.

And if you conveniently ignore the first term then 3, 7, 127, ... does match your claim, but then 31, 2147483647, ... fails your claim. You can't have it both ways.

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