A134596 The largest n-digit primeval number A072857.

2, 37, 137, 1379, 13679, 123479, 1234679, 12345679, 102345679, 1123456789, 10123456789

Offset: 1

Author

N. J. A. Sloane, Jan 25 2008

Keywords

• nonn
• base
• more

Comments

Former definition: The least n-digit number m (i.e., m >= 10^(n-1)) which yields A076730(n) = the maximum, for m < 10^n, of A039993(m) = number of primes that can be formed using some or all digits of m.

Subsequence of A072857 consisting of the largest terms of given length. - M. F. Hasler, Mar 12 2014

Links

• M. Keith, Integers containing many embedded primes

Crossrefs

Cf. A039993, A072857, A076730, A134597, A076449.

Programs

PARI

A134596(n,A=A072857)=vecmax(select(t->logint(t,10)+1==n,A)) \\ where A072857 must comprise all n digit terms of that sequence. - M. F. Hasler, Oct 14 2019

Python

# see linked program in A076449

Formula

a(n) = max { m in A072857, m < 10^n }. - M. F. Hasler, Mar 12 2014

Extensions

Link fixed by Charles R Greathouse IV, Aug 13 2009

Definition reworded and values of a(6)-a(11) added by M. F. Hasler, Mar 11 2014