“ Best
Thomas Papanikolaou
Catalan constant to 1500000 digits computed on October 26, 1996 by using a Sun Sparc20 in 7 day 7 hour 14 min 52 sec 71 hsec The algorithm used is the standard series for Catalan, accelerated by an Euler transform as shown by
Greg Fee, ACM 1990, Proceedings of the ISAAC conference, 1990, p. 157
The algorithm was implemented using the LiDIA library for computational number theory and it will be part of the multiprecision floating-point arithmetic of the package in release 1.4. ”