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A038623
Smallest prime p such that p/pi(p)>=n.
16
2, 2, 37, 127, 347, 1087, 3109, 8419, 24317, 64553, 175211, 480881, 1304707, 3523901, 9558533, 25874843, 70115473, 189961529, 514272533, 1394193607, 3779851091, 10246935679, 27788566133, 75370121191, 204475052401, 554805820711, 1505578023841, 4086199302113
OFFSET
1,1
LINKS
FORMULA
a(n) = exp(n + 1 + o(1)). - Charles R Greathouse IV, Oct 15 2016
EXAMPLE
pi(37)=12 and a(3)=37 is the smallest prime >= 3*12.
MATHEMATICA
Prime[Join[{k = 1}, Table[While[Prime[k]/k < n, k++]; k, {n, 2, 18}]]] (* Jayanta Basu, Jul 10 2013 *)
PROG
(PARI) k=n=1; forprime(p=2, , while(p/k>=n, print1(p", "); n++); k++) \\ Charles R Greathouse IV, Oct 15 2016
CROSSREFS
Essentially the same as A062743.
a(n) = prime(A038624(n)).
Sequence in context: A298993 A267345 A059523 * A001121 A202711 A222668
KEYWORD
nonn
AUTHOR
EXTENSIONS
Edited by N. J. A. Sloane, Jun 30 2008 at the suggestion of R. J. Mathar
a(24)-a(28) from David W. Wilson, Apr 25 2017
a(29)-a(50) obtained from the values of A038625 computed by Jan Büthe. - Giovanni Resta, Sep 01 2018
STATUS
approved