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A165689 Numbers n such that pi(n) = (1/10)*n. 0
64540, 64580, 64610, 64620, 64650, 64690, 64700, 64710, 64720 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A057809. For each positive integer m, set of the numbers n such that pi(n)=(1/10^m)*n is a finite set. I guess that all these sets are nonempty. What is the smallest number n such that pi(n) = (1/100)*n?

LINKS

Table of n, a(n) for n=1..9.

MATHEMATICA

Select[10 Range[10000], PrimePi[ # ] == 1/10 # &]

PROG

(PARI) forcomposite(n=1, 1e5, if(10*primepi(n) == n, print1(n, ", "))) \\ Altug Alkan, Dec 18 2015

CROSSREFS

Cf. A057809.

Sequence in context: A234128 A205631 A205333 * A236469 A203712 A061738

Adjacent sequences:  A165686 A165687 A165688 * A165690 A165691 A165692

KEYWORD

fini,full,nonn

AUTHOR

Farideh Firoozbakht, Oct 06 2009

STATUS

approved

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Last modified November 14 09:51 EST 2019. Contains 329111 sequences. (Running on oeis4.)