A050284 a(n) is the starting position of the first occurrence of a string of (at least) n '5's in the decimal expansion of Pi.

4, 130, 177, 24466, 24466, 244453, 3517236, 168743355, 5050944965, 7644991298, 157675736216, 1618922020656, 7604259624808, 7604259624808

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn
• base
• more

Comments

This sequence has a(4) = a(5) = A096759(5) < A096759(4). As can be seen from a(1) = 4 (referring to the '5' in 3.1415...), position p means the string starts at the p-th digit after the decimal point. - M. F. Hasler, Apr 13 2019

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

a(15) > 22*10^12. - Dmitry Petukhov, Jan 29 2020

Links

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

Crossrefs

Cf. A096759 (variant), ...A050283, A050285... (analog for digits ..., 4, 6, ...).

Extensions

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

Typo in a(10) corrected by Giovanni Resta, Oct 02 2019

a(11)-a(14) added by Dmitry Petukhov, Jan 12 2020