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A comment on Socat: “the hard coded 1024 bit DH p parameter was not prime”. Parent comment

Re:Socat: “the hard coded 1024 bit DH p parameter was not pr... by 542458 on Monday February 01, 2016 @05:28PM (#11016103)
Oh jeez. That non-prime is evenly divisible by 271 and 13597 (among other things).
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Re:Socat: “the hard coded 1024 bit DH p parameter was not pr... by gus_massa on Monday February 01, 2016 @06:45PM (#11016618)
Let's assume it's not malice. Can it be a typo? Is there a prime with a low Levenshtein distance in hex of the old no-prime number?

(Is there a always a prime within a low distance from any number?)

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Re:Socat: “the hard coded 1024 bit DH p parameter was not pr... by lifthrasiir on Monday February 01, 2016 @07:51PM (#11016960)
I've tested some of them with PARI/GP. There is no probable prime with the Hamming distance 1. There are several (probably 3--400, haven't exhaustively listed) probable primes with the Hamming distance 2 (p ^ (1<<30) ^ (1<<14) is one example).
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Re:Socat: “the hard coded 1024 bit DH p parameter was not pr... by bonzini on Tuesday February 02, 2016 @04:57PM (#11022994)
About 1 in 700 1024-bit numbers is prime. There are 1023512 Hamming-distance 2 numbers for a 1024-bit number, about 750 of them will be prime.

If you found no Hamming distance 1 primes (expected: 0.68) and 3-400 Hamming distance 2 primes (expected: 750), this is one really* bad "prime"...

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Re:Socat: “the hard coded 1024 bit DH p parameter was not pr... by kazagistar on Tuesday February 02, 2016 @12:21PM (#11020803)
Well, the provided command takes 2.5 min to for pari to test the given "prime" on my computer. There are 16*256 numbers with a single hex digit mutation from the number given.

Anyone got a cluster laying around?

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