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A039506
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Number of cluster primes less than 10^n.
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6
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3, 23, 99, 420, 1807, 8287, 40017, 202208, 1059807, 5736717, 31911465, 182019293, 1060723057
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OFFSET
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1,1
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COMMENTS
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The Blecksmith paper gives incorrect values of a(n) for n>8. - T. D. Noe, Jul 21 2006
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LINKS
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Richard Blecksmith, Paul Erdős and J. L. Selfridge, Cluster Primes, Amer. Math. Monthly, 106 (1999), 43-48.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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