hi,

Is the following statement wrong?

If C(p-1,(p-1)/2) mod p = p-1 then p is prime

Exemple :

p=7

C(6,3)=20

C(6,3) mod 7 = 6

If it is correct how can we prove it?

Thank you very much for any comment.

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- April 12th 2013, 06:05 PMMouhahaPrime or not?
hi,

Is the following statement wrong?

If C(p-1,(p-1)/2) mod p = p-1 then p is prime

Exemple :

p=7

C(6,3)=20

C(6,3) mod 7 = 6

If it is correct how can we prove it?

Thank you very much for any comment. - April 13th 2013, 02:44 PMMouhahaRe: Prime or not?
Any counterexample?

5 is prime C(4,2) mod 5=1

My claim is that if C(p-1,(p-1/2)) mod p= p-1 THEN p is prime. - April 16th 2013, 06:37 AMMouhahaRe: Prime or not?
The fisrt counterexample was found.

p=5097 is composite

I do not know if there are other counterexamples.