Equations (24.5.3) and (24.5.4) enable
and
to be computed by recurrence. For higher values
of
more efficient methods are available. For example, the tangent numbers
can be generated by simple recurrence relations obtained from
(24.15.3), then (24.15.4) is applied. A similar method
can be used for the Euler numbers based on (4.19.5). For details see
Knuth and Buckholtz (1967).
For number-theoretic applications it is important to compute
for
; in particular to find the
irregular pairs
for which
.
We list here three methods, arranged in increasing order of efficiency.
Tanner and Wagstaff (1987) derives a congruence
for Bernoulli
numbers in terms of sums of powers. See also §24.10(iii).