Trying to follow the algorithm to calculate Bernulli number. On the page 4 it is written:
$$d = \prod_{p-1|m}p$$
which in my opinion means that I have to find all the numbers $p-1$ that divide $m$ and then multiplies all these $p$.
But on the page 5 for the example of $m=50$ they calculate something strange: d = 2 * 3 * 11. This is strange because 50 has 5 divisors (without 1) and they only multiply 3 numbers. Where I am wrong?
You have to compute the product of all primes $p$ with $(p-1) | 50$ and these are $2,3,11$. Or the other way round: look for the proper divisiors $q$ of $50$ with $q+1$ prime; cf. the section von Staudt - Clausen theorem with $m=2n$.