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A039507
Number of odd non-cluster primes less than 10^n.
3
0, 1, 68, 808, 7784, 70210, 624561, 5559246, 49787726, 449315793, 4086143347, 37425892724, 345004813781
OFFSET
1,3
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.
FORMULA
a(n) = A006880(n) - A039506(n) - 1. - T. D. Noe, Jul 21 2006
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Christian G. Bower, Feb 15 1999
EXTENSIONS
Corrected by T. D. Noe, Jul 21 2006
STATUS
approved