* src/float/transcendental/cl_LF_pi.cc (compute_pi_ramanujan_163_fast):
Compute series coefficients on demand, using a series stream object.
* src/float/transcendental/cl_LF_zeta3.cc (zeta3): Likewise.
* src/float/transcendental/cl_LF_catalanconst.cc
(compute_catalanconst_ramanujan_fast): Likewise.
(compute_catalanconst_lupas): New function.
(compute_catalanconst): Simplify, based on new benchmark.