Distinguish pq Prime Cases: Algorithm for ppt

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Dragonfall
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Given [itex]pq[/itex] where [itex]p < q[/itex] are prime, but either ([itex]p \equiv 1 \mod 4[/itex] and [itex]q \equiv 3 \mod 4[/itex]) or ([itex]p \equiv 3 \mod 4[/itex] and [itex]q \equiv 1 \mod 4[/itex]).

Is there a ppt algorithm that will distinguish the two possibilities?
 
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pasmith said:
More importantly, for how many primes [itex]q[/itex] is it true that [itex]q[/itex] is divisible by 3?

The definition of prime says a prime is divisible only by itself and 1, hence only 3 fits for the occasion :P
 
You people must be some kind of super geniuses.
 
Dragonfall said:
Given [itex]pq[/itex] where [itex]p < q[/itex] are prime, but either ([itex]p \equiv 1 \mod 4[/itex] and [itex]q \equiv 3 \mod 4[/itex]) or ([itex]p \equiv 3 \mod 4[/itex] and [itex]q \equiv 1 \mod 4[/itex]).

Is there a ppt algorithm that will distinguish the two possibilities?

I'm not familiar with one, but I'm not too familiar with these sorts of things. Is this a cryptography problem? I thought that factoring primes was always more than polynomial time.

PeroK said:
How many primes are [itex]\equiv 1 \mod 3[/itex]

Infinite? I can't prove it. But why?
 
There are indeed infinitely many primes that are 1 mod 3. But that's not relevant.

If this problem is hard then it would make a very simple bit-commitment scheme.
 
PeroK said:
How many primes are [itex]\equiv 1 \mod 3[/itex]

pasmith said:
More importantly, for how many primes [itex]q[/itex] is it true that [itex]q[/itex] is divisible by 3?

I should clarify, for the benefit of future readers, that these were in response to the unedited original post which read

Dragonfall said:
Given [itex]pq[/itex] where [itex]p < q[/itex] are prime, but either ([itex]p \equiv 1 \mod 3[/itex] and [itex]q \equiv 3 \mod 3[/itex]) or ([itex]p \equiv 3 \mod 3[/itex] and [itex]q \equiv 1 \mod 3[/itex]).

Is there a ppt algorithm that will distinguish the two possibilities?
 
Ahh, I was quite confused.
 
Somebody clean up all the useless replies here please.