In article _Bq0h.22$gf5.1@trndny01, Chess One wrote:
[...] - it is extraordinary to me that 100k
sequenced datum, which are non-musical could be undertaken - I must suppose
that he calculated the next in sequence [rather than any feat of memory] and
wonder how long it took him to do this overall as well as the typical
interval from one digit to the next?

No, not a chance. There are humanly-computable ways of finding
specific digits in a hexadecimal expansion [and so in binary or octal]
of pi, so you could plausibly ask a skilled mathematician to tell you [eg]
the 1234567th such digit; but no known way of doing it in decimal. If
there were, I'd guess it would take hours, even with a calculator, to
get each digit. Calculating pi to even a few hundred places of decimals
without computer assistance is years of work.

We can safely assume that Akira Haraguchi simply has a somewhat
unusual memory.

--
Andy Walker, School of MathSci., Univ. of Nott'm, UK.