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A090977 Least k such that k*prime(k) > 10^n. 1
3, 7, 17, 48, 134, 382, 1115, 3287, 9786, 29296, 88181, 266694, 809599, 2465574, 7528976, 23045352, 70684657, 217196605, 668461874, 2060257099, 6358076827, 19644205359, 60757729194, 188099056251, 582846849914, 1807483210259, 5609430824151, 17420628067997 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Does lim_{n->infinity} a(n+1)/a(n) exist? If so, is the limit Pi? - Ryan Propper, Sep 15 2005

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..36

EXAMPLE

a(3) = 17 as 17*prime(17) = 17*59 = 1003 > 10^3.

MAPLE

for n from 1 to 11 do b:=proc(k) if k*ithprime(k)>10^n then k else fi end: a[n]:=[seq(b(k), k=1..100000)][1]: od: seq(a[n], n=1..11); # Emeric Deutsch, Aug 04 2005

MATHEMATICA

n = 1; For[k = 1, k > 0, k++, If[k*Prime[k] > 10^n, Print[k]; n++ ]] (* Ryan Propper, Sep 15 2005 *)

CROSSREFS

Sequence in context: A179944 A071985 A181419 * A014144 A247183 A321139

Adjacent sequences:  A090974 A090975 A090976 * A090978 A090979 A090980

KEYWORD

base,nonn,more

AUTHOR

Amarnath Murthy, Jan 04 2004

EXTENSIONS

More terms from Emeric Deutsch, Aug 04 2005

More terms from Ryan Propper, Sep 15 2005

a(20)-a(28) from Chai Wah Wu, Apr 29 2018

STATUS

approved

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Last modified February 16 08:26 EST 2019. Contains 320159 sequences. (Running on oeis4.)