A049522 Smallest starting index for a run of at least n consecutive equal digits in decimal expansion of Pi.

1, 25, 154, 763, 763, 763, 710101, 22931746, 24658602, 386980413, 15647738229, 368299898267, 2164164669333, 5758910552710, 28642224609577, 28642224609577, 28642224609577

Offset: 1

Author

Harvey P. Dale

Keywords

• nonn
• base
• more

Comments

Digits 3,1,4,1,5,... are indexed 1,2,3,4,5,...

a(11) > 2*10^9. - M. F. Hasler, Mar 21 2017

a(12) > 99*10^9. - Giovanni Resta, Oct 02 2019

a(15) > 12*10^12. - Dmitry Petukhov, Dec 30 2019

a(18) > 50*10^12. - Dmitry Petukhov, Oct 30 2021

Links

• Pi search engine (searches initial 2 x 10^9 digits of Pi)
• Dave Andersen, Pi-Search Page (searches initial 2 x 10^8 digits of Pi)
• Yasumasa Kanada, Statistical Distribution Information, Home page, Computer Centre, The University of Tokyo.
• Timothy Mullican, 50 trillion digits of pi
• PI-world Site, The digits and Statistics for 12 trillion digits of PI [archived page]
• Peter Trüb, 22.4 trillion digits of pi
• Eric Weisstein's World of Mathematics, Pi Digits.

Crossrefs

Cf. A049514-A049523.

Compare A049523: the first run of six 9's occurs (with starting index 763) before any runs of exactly four or exactly five equal digits.

Cf. A084145 (digit with this starting index).

Extensions

More terms from Rick L. Shepherd, May 22 2003

a(10) from Felix Fröhlich, Oct 06 2016

a(11) from Giovanni Resta, Oct 02 2019

a(12)-a(14) added by Dmitry Petukhov, Dec 30 2019

a(15)-a(17) from Dmitry Petukhov, Oct 30 2021

a(15)-a(17) had off-by-1 error, corrected by Mike Keith, Feb 03 2025