A227529 Copeland-Erdős constant primes (concatenation of entries (digits) of A033308 is prime).

2, 23, 2357, 23571113171

Offset: 1

Author

Eric W. Weisstein, Jul 14 2013

Keywords

• base
• nonn
• hard

Comments

Primes obtained by taking consecutive decimal digits (starting with the first) of the Copeland-Erdős constant.

The next terms are too big to display: a(5) = 235711131...6917017097 (353 digits), a(6) = 235711131...1701709719 (355 digits), ...

See A227530 for an equivalent but more compact way of listing the terms, namely, by giving the number of digits of the constant A033308 that must be taken to get a prime. - M. F. Hasler, Apr 24 2017

Links

• Eric W. Weisstein, Table of n, a(n) for n = 1..7
• Hans Havermann and Eric W. Weisstein (first 11 terms), Table of n, a(n) for n = 1..14
• Eric Weisstein's World of Mathematics, Copeland-Erdős Constant

Crossrefs

Cf. A227530 (number of decimal digits in the n-th Copeland-Erdős prime).

Cf. A019518, A069151.

Cf. A033308 (Decimal expansion of Copeland-Erdős constant: concatenate primes).