An enormous chunk of pi.

Computation of the digits of pi ([Pi]), the number representing the ratio of a circle's circumference to its diameter, has taken a giant leap forward. Computer scientist Yasumasa Kanada and his coworkers at the University of Tokyo Computer Centre last month reported calculating 51.5396 billion decimal digits, besting their previous world record of 6.4 billion digits (SN: 10/28/95, p. 279). The calculation was done twice, with two different methods, as a check. One computation required 29 hours and the other 37 hours on a multiprocessor Hitachi SR2201 computer.

This is a landmark achievement, says mathematician Jonathan M. Borwein of Simon Fraser University in Burnaby, British Columbia. The main reason for the greatly improved performance was the division of the task among 1,024 processors, which cut computation time considerably.

Kanada's analysis of the first 50 billion digits of pi shows that the number 8 appears most often (5,000,117,637 times) and 3 least often (4,999,914,405 times).

By using additional computer time, the record can be pushed a little higher, Kanada says. Reaching 100 billion digits, however, would require a much more powerful computer with additional memory.