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a(n) is the starting position of the first occurrence of a string of at least n 1's in the decimal expansion of Pi.
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%I #33 Sep 20 2022 02:38:46

%S 1,94,153,12700,32788,255945,4657555,159090113,812432526,3961184001,

%T 15647738228,1041032609981,3907688331257,68635742334547

%N a(n) is the starting position of the first occurrence of a string of at least n 1's in the decimal expansion of Pi.

%C Presently identical to A096755, which is the first occurrences of exactly n 1's in the digits of Pi. Will differ as soon as there's some a(n) = a(n+1) and equivalently, A035117(n) > A035117(n+1). - _M. F. Hasler_, Mar 17 2017

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

%H PI-world Site, <a href="https://web.archive.org/web/20140130074648/http://piworld.calico.jp/epidigits.html">The digits and Statistics for 12 trillion digits of PI</a> [archived page]

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiDigits.html">Pi Digits.</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>

%Y Cf. A000796 (decimal expansion (or digits) of Pi).

%Y Cf. A035117 (this), A050281 (n '2's), A050282, A050283, A050284, A050286, A050287, A048940 (n '9's).

%Y Cf. A096755 (exactly n '1's), A096756, A096757, A096758, A096759, A096760, A096761, A096762, A096763 (exactly n '9's), A050279 (exactly n '0's).

%Y Cf. A121280 = A068987 - 1 (position of "123...n" in Pi's decimals).

%Y Cf. A176341 (first occurrence of n in Pi's digits).

%K nonn,base,more

%O 1,2

%A Leonardo Bitran (lbitran(AT)reuna.cl)

%E More terms from Colin Martin (cbmartin(AT)tpg.com.au), Mar 03 2002

%E Edited by _N. J. A. Sloane_ at the suggestion of _Andrew S. Plewe_, May 27 2007

%E Edited, after re-establishing A096755, by _M. F. Hasler_, Mar 17 2017

%E a(11) from _Giovanni Resta_, Sep 30 2019

%E a(12) from Yasumasa Kanada Laboratory, 2002 and a(13) from Shigeru Kondo, 2011, added by _Dmitry Petukhov_, Dec 27 2019

%E a(14) from _Dmitry Petukhov_, Sep 19 2022