Talk:Lucas-Lehmer Test

I always thought 11 was a prime. Guess not. If q=11 Excel says L9 is 1736.


 * Yes, that is perfectly correct. $$11$$ is prime. However, $$2^{11} - 1$$ is not prime ($$2047 = 23 \times 89$$), which is why $$L_9 \ne 0$$. --prime mover 22:14, 18 September 2010 (UTC)