A121044 Greatest cluster prime less than 10^n.

7, 89, 983, 9931, 99991, 999331, 9997879, 99999551, 999998693, 9999995363, 99999976319, 999999998533, 9999999954787

Offset

1,1

Comments

These numbers are useful for generating intermediate cluster primes because the best algorithm for generating cluster primes requires starting with a known cluster prime.

Links

Table of n, a(n) for n=1..13.

Crossrefs

Cf. A038134 (cluster primes), A039506 (number of cluster primes < 10^n), A121045.

Sequence in context: A178006 A053302 A068877 * A107109 A089771 A249448

Adjacent sequences: A121041 A121042 A121043 * A121045 A121046 A121047

Keyword

nonn

Author

T. D. Noe, Jul 21 2006

Status

approved