The functions
,
,
and
may be extended to noninteger values of
by generalizing
, and supplementing
(33.6.5) by a formula derived from (33.2.8) with
expanded via (13.2.42).
These functions may also be continued analytically to complex values of
,
, and
. The quantities
,
, and
, given by (33.2.6),
(33.2.10), and (33.4.1), respectively, must be defined
consistently so that
and