A050286 Starting position of the first occurrence of a string of at least n '7's in the decimal expansion of Pi.

13, 559, 1589, 1589, 162248, 399579, 3346228, 24658601, 24658601, 22869046249, 165431035708, 368299898266, 10541103245815, 14793486898235, 46970519777308

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn
• base
• more

Comments

a(10) > 2*10^9 according to the SubIdiom.com/pi search engine. - M. F. Hasler, Apr 13 2019

a(11) > 99*10^9. - Giovanni Resta, Oct 02 2019

a(15) > 22*10^12. - Dmitry Petukhov, Jan 27 2020

a(16) > 50*10^12. - Dmitry Petukhov, Oct 30 2021

Links

• Timothy Mullican, 50 trillion digits of pi
• Peter Trüb, 22.4 trillion digits of pi
• Eric Weisstein's World of Mathematics, Pi Digits.

Crossrefs

Cf. A000796: Decimal expansion (or digits) of Pi.

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).

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).

Cf. A176341 (first occurrence of n).

Cf. A121280 = A068987 - 1 (first occurrence of concatenate(1,...,n)).

Formula

a(n) = min { A096761(k); k >= n }. - M. F. Hasler, Mar 19 2017

Extensions

Edited by M. F. Hasler, Mar 19 2017

a(10) from Giovanni Resta, Oct 02 2019

a(11)-a(13) added by Dmitry Petukhov, Jan 13 2020

a(14) from Dmitry Petukhov, Jan 27 2020

a(15) from Dmitry Petukhov, Oct 30 2021