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A105466 Number of irregular primes less than or equal to the m-th prime, where m = floor(exp(n)). 2
0, 0, 3, 9, 58, 159, 440, 1166, 3202, 8655 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Limit_{n->inf.} a(n)/e^n = 1-e^(-1/2).

MATHEMATICA

ip={ the list of irregular primes to 12 million }; Table[ Length[ Select[ip, # < Prime[Floor[E^n]] &]], {n, 10}]

CROSSREFS

Cf. A105457, A105461.

Sequence in context: A128681 A040175 A192252 * A018504 A140812 A202210

Adjacent sequences:  A105463 A105464 A105465 * A105467 A105468 A105469

KEYWORD

hard,nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 07 2005

EXTENSIONS

Definition clarified by N. J. A. Sloane (njas(AT)research.att.com), Jan 19 2009

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.