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URL: https://oeis.org/A105468

⇱ A105468 - OEIS

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A105468
Number of irregular primes less than or equal to the 10^n-th prime.
1
0, 30, 392, 3935, 39400, 393737, 3933421, 39339651
OFFSET
1,2
COMMENTS
Limit_{n->inf.} a(n)/10^n -> 1-e^(-1/2).
MATHEMATICA
ip={ the list of irregular primes to 12 million }; Table[ Length[ Select[ip, # <= Prime[10^n] &]], {n, 5}]
CROSSREFS
KEYWORD
hard,nonn,more
AUTHOR
Robert G. Wilson v, Apr 07 2005
EXTENSIONS
Data corrected and a(6)-a(8) added by Amiram Eldar, Mar 05 2019
STATUS
approved