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A039506
Number of cluster primes less than 10^n.
6
3, 23, 99, 420, 1807, 8287, 40017, 202208, 1059807, 5736717, 31911465, 182019293, 1060723057
OFFSET
1,1
COMMENTS
The Blecksmith paper gives incorrect values of a(n) for n>8. - T. D. Noe, Jul 21 2006
LINKS
Richard Blecksmith, Paul Erdős and J. L. Selfridge, Cluster Primes, Amer. Math. Monthly, 106 (1999), 43-48.
Eric Weisstein's World of Mathematics, Cluster Prime.
CROSSREFS
Cf. A121044, A121045 (cluster primes near 10^n).
Sequence in context: A301580 A112459 A197303 * A196970 A197557 A225671
KEYWORD
nonn,more
AUTHOR
Christian G. Bower, Feb 15 1999
EXTENSIONS
Corrected by T. D. Noe, Jul 21 2006
STATUS
approved