I need help on proving something

I need help on proving something

Posers and Puzzles

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s
Slappy slap slap

Under your bed...

Joined
22 Oct 05
Moves
70042
25 Nov 05

3n^2+3n+1 will either produce a prime congruent to 1 (mod 6) or the factors of the number produced will all be congruent to 1 (mod 6). I can show that any number that will be produced by it is congruent to 1 (mod 6) but I can't show that factors will be. Contradiction proofs will not work because any number congruent to 5 (mod 6) will also work. Don't reply if you don't know what (mod 🙄 means.

T
Kupikupopo!

Out of my mind

Joined
25 Oct 02
Moves
20443
25 Nov 05

Originally posted by slappy115
3n^2+3n+1 will either produce a prime congruent to 1 (mod 6) or the factors of the number produced will all be congruent to 1 (mod 6). I can show that any number that will be produced by it is congruent to 1 (mod 6) but I can't show that factors will be. Contradiction proofs will not work because any number congruent to 5 (mod 6) will also work. Don't reply if you don't know what (mod 🙄 means.
(6k+5)(6l+1) = 36kl + 30l + 6k +5 = 6m+5

This shows that if only one of the factors of a number is 5 mod 6, then the number itself will be 5 mod 6.

(6k+5)(6l+5) = 36kl + 30k + 30l + 25 = 6m+1

This shows that if two factors are 5 mod 6, the numbe will be 1 mod 6.

From these two lines and what you showed (result is 1 mod 6) we can conclude that IF there are factors that are 5 mod 6, they will come in pairs (even amounts).

That's as far as I could reason in my 5 min break :p

s
Slappy slap slap

Under your bed...

Joined
22 Oct 05
Moves
70042
26 Nov 05

Thanks for the input. I've tried looking at that before and have come to the conclusion too. That, however, doesn't show the factors are congruent to 1 (mod 6) but shows that it is possible for the factors to be congruent to 5 (mod 6) since both 1 and 5 are relatively prime to 6.

T
Kupikupopo!

Out of my mind

Joined
25 Oct 02
Moves
20443
27 Nov 05

Yeah, but now you know the factors 5 mod 6 must come in pairs 🙂

I don't know if that's something usefull though. I'm trying a different method now, I'm changing the formula mod 6, in the hope I can factorize it...so far no luck.

s
Slappy slap slap

Under your bed...

Joined
22 Oct 05
Moves
70042
27 Nov 05

I've also tried a bunch of different methods and ideas to show the factors can't be congruent to 1 (mod 6) and contradictions will not work since the product of two numbers congruent to 5 (mod 6) produce a number congruent to 1 (mod 6). And thanks for the help, I really appreciate it.

f

Joined
01 May 05
Moves
390
28 Nov 05

Originally posted by slappy115
3n^2+3n+1 will either produce a prime congruent to 1 (mod 6) or the factors of the number produced will all be congruent to 1 (mod 6). I can show that any number that will be produced by it is congruent to 1 (mod 6) but I can't show that factors will be. Contradiction proofs will not work because any number congruent to 5 (mod 6) will also work. Don't reply if you don't know what (mod 🙄 means.
WARNING: Conclusions that have no practical value may follow!

3n^2+3n=6(n+1)(n/2)
3n^2+3n=3n(1+n)

3n^2+3n+1=(6a+1)(6y+1)
n(n+1)=2(a+y+6ay)
a=(91-y)/(1+6y)

Just random conclusions...

s
Slappy slap slap

Under your bed...

Joined
22 Oct 05
Moves
70042
28 Nov 05

Thanks for your input. I will take a look at these and see if they help me with what I have.