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grammar in the title, then cancelled misunderstanding from my side

If $\binom{2p}{p}$ is $(-1)^{p-1} \bmod 2p+1$ is then $2p+1$ prime?

Let $p$ be a positive integer; if $2p+1$ is prime then it is easily checked that $$(2p+1)\mid\left(\binom{2p}{p}+(-1)^{p-1}\right);$$

conversely I conjecture that if the above divisibility assumption holds, then $2p+1$ is a prime number. Is this true?