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A086688 Number of primes < prime(n)^3. 0
4, 9, 30, 68, 217, 327, 656, 882, 1457, 2707, 3228, 5194, 6850, 7789, 9916, 13746, 18411, 20179, 26062, 30597, 32984, 40991, 46959, 56924, 72217, 80725, 85182, 94695, 99669, 110127, 152280, 165951, 187910, 195660, 237427, 246434, 274614 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..37.

FORMULA

a(n) = A038098(prime(n)). - R. J. Mathar, Sep 15 2012

PROG

(PARI) primeslessp3(n) = \primes less than primes cubed { sr=0; forprime(x=2, n, y=pi(x^3); sr+=1.0/y; print1(y", "); ); print(); print(sr) } pi(n) = { c=0; forprime(x=2, n, c++); return(c) }

CROSSREFS

Sequence in context: A091658 A297960 A295910 * A309295 A151270 A149113

Adjacent sequences:  A086685 A086686 A086687 * A086689 A086690 A086691

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Jul 28 2003

STATUS

approved

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Last modified July 24 06:56 EDT 2021. Contains 346273 sequences. (Running on oeis4.)