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A217691 Primes in A217689. 3
2, 3, 19, 23, 31, 43, 59, 61, 73, 83, 103, 107, 109, 113, 151, 163, 179, 181, 197, 199, 233, 241, 269, 271, 277, 281, 283, 313, 317, 349, 353, 379, 383, 409, 421, 433, 443, 449, 461, 463, 503, 509, 523, 571, 577, 593, 599, 601, 617, 619, 643, 647, 659, 661, 677 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Apart from the initial 2, the odd terms of A217689. - M. F. Hasler, Oct 19 2012

LINKS

Table of n, a(n) for n=1..55.

FORMULA

If A(n) is the number of terms not exceeding n, then heuristically A(n) is equivalent to log(2)*pi(n), as n tends to infinity. Practically, an approximation of A(n)is given by the expression n*log(2)/log(n*log(n)).

CROSSREFS

Cf. A217689.

Sequence in context: A082012 A059675 A128353 * A109418 A038957 A141750

Adjacent sequences:  A217688 A217689 A217690 * A217692 A217693 A217694

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Oct 11 2012

STATUS

approved

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Last modified December 9 07:21 EST 2021. Contains 349627 sequences. (Running on oeis4.)