A081876 - OEIS

%I #41 Oct 28 2021 02:02:44

%S 9,137,2120,3496,88008,176451,25198140,50366472,1660042751,7902183159,

%T 260816757309,1142905318634,17475119650043,43420162171515

%N a(n) is the starting position of the second occurrence of a string of the initial n decimal digits of Pi in the decimal expansion of Pi.

%C The digits 3 1 4 1 5 ... are labeled 0, 1, 2, 3, 4, ...

%C a(9) > 10^8. - _Robert G. Wilson v_, May 09 2003

%C a(15) > 50*10^12. - _Dmitry Petukhov_, Oct 27 2021

%D Alfred S. Posamentier & Ingmar Lehmann, A Biography of the World's Most Mysterious Number, Prometheus Books, Amherst, NY 2004, page 134.

%H Dave Andersen, <a href="http://www.angio.net/pi/piquery">The Pi-Search Page</a>

%H Yasumasa Kanada Laboratory Home Page, Computer Centre, The University of Tokyo, <a href="http://www.super-computing.org/pi-decimal_current.html">Statistical Distribution Information</a>.

%H Timothy Mullican, <a href="https://storage.googleapis.com/pi50t/index.html">50 trillion digits of pi</a>

%H Harry J. Smith, <a href="http://harry-j-smith-memorial.com/Pi/">Computing Pi</a> [Broken link]

%H Harry J. Smith, <a href="http://www.oocities.org/hjsmithh/Pi/">Computing Pi</a>

%H Peter Trüb, <a href="https://pi2e.ch/blog/2017/03/10/pi-digits-download/">22.4 trillion digits of pi</a>

%H <a href="http://www.subidiom.com/pi/">Pi search engine</a>

%Y Cf. A000796, A048940, A166028.

%K nonn,base,more

%O 1,1

%A _Harry J. Smith_, Apr 12 2003

%E a(9) from _Felix Fröhlich_, Oct 04 2016

%E a(10)-a(11) from _Andreas Stiller_, Apr 08 2019

%E a(12) from _Robert G. Wilson v_, Oct 21 2004

%E a(13) from _Dmitry Petukhov_, Jan 27 2020

%E a(14) from _Dmitry Petukhov_, Oct 27 2021