**Irregular primes: p is regular if and only if the numerators of the Bernoulli numbers B_2, B_4, ..., B_{p-3} (A000367) are not divisible by p.**

*37, 59, 67, 101, 103, 131, 149, 157, 233, 257, 263, 271, 283, 293, 307, 311, 347, 353*

*1 seqfan posts*

Index of A-numbers in seqfan: by ascending order by month by frequency by keyword

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