If p divides the numerator of the Bernoulli number for
,
is called an irregular pair. For p < 30000, the irregular pairs of various forms are p = 16843 for
,
,
,
for
.
Bernoulli Number, Irregular Prime
Johnson, W. "Irregular Primes and Cyclotomic Invariants." Math. Comput. 29, 113-120, 1975.