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%I #33 Oct 30 2021 05:00:23
%S 13,559,1589,1589,162248,399579,3346228,24658601,24658601,22869046249,
%T 165431035708,368299898266,10541103245815,14793486898235,
%U 46970519777308
%N Starting position of the first occurrence of a string of at least n '7's in the decimal expansion of Pi.
%C a(10) > 2*10^9 according to the SubIdiom.com/pi search engine. - _M. F. Hasler_, Apr 13 2019
%C a(11) > 99*10^9. - _Giovanni Resta_, Oct 02 2019
%C a(15) > 22*10^12. - _Dmitry Petukhov_, Jan 27 2020
%C a(16) > 50*10^12. - _Dmitry Petukhov_, Oct 30 2021
%H Timothy Mullican, <a href="https://storage.googleapis.com/pi50t/index.html">50 trillion digits of 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 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiDigits.html">Pi Digits</a>.
%F a(n) = min { A096761(k); k >= n }. - _M. F. Hasler_, Mar 19 2017
%Y Cf. A000796: Decimal expansion (or digits) of Pi.
%Y First occurrence of n times the same digit: A035117 (n '1's), A050281 (n '2's), A050282, A050283, A050284, A050286, A050287, A048940 (n '9's).
%Y First occurrence of exactly n times the same digit: A096755 (exactly n '1's), A096756, A096757, A096758, A096759, A096760, A096761, A096762, A096763 (exactly n '9's), A050279 (exactly n '0's).
%Y Cf. A176341 (first occurrence of n).
%Y Cf. A121280 = A068987 - 1 (first occurrence of concatenate(1,...,n)).
%K nonn,base,more
%O 1,1
%A _Eric W. Weisstein_
%E Edited by _M. F. Hasler_, Mar 19 2017
%E a(10) from _Giovanni Resta_, Oct 02 2019
%E a(11)-a(13) added by _Dmitry Petukhov_, Jan 13 2020
%E a(14) from _Dmitry Petukhov_, Jan 27 2020
%E a(15) from _Dmitry Petukhov_, Oct 30 2021
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