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A163161 Values of n at which the sequence A161865/A161867 equals 1/2. 0
5, 9, 14, 30, 44, 47, 64, 67, 72, 89, 99, 124, 125, 194, 198, 200, 208, 213, 214, 249, 267, 270, 320, 333, 372, 373, 374, 393, 455, 460, 475, 519, 586, 603, 643, 701, 704, 712, 770, 774, 789, 814, 825, 828, 836, 891, 906, 930, 941, 970, 974, 982, 983, 988, 1022 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The corresponding sequence for primes is A144264, and the ratio is given by sequences A161621/A161622.

LINKS

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

MATHEMATICA

t1 = Table[ ((2n+1) - (PrimePi[(n+1)^2] - PrimePi[n^2]))/((4n+4)- (PrimePi[(n+2)^2] - PrimePi[n^2])), {n, 1, 100}]; t2= Position[t1, 1/2]; [From Daniel Tisdale, Jul 24 2009]

CROSSREFS

Sequence in context: A169872 A115380 A107980 * A188358 A228218 A314993

Adjacent sequences:  A163158 A163159 A163160 * A163162 A163163 A163164

KEYWORD

nonn

AUTHOR

Daniel Tisdale, Jul 21 2009, Jul 24 2009

EXTENSIONS

Corrected by the author, Jul 25 2009

Extended beyond 194 by R. J. Mathar, Sep 27 2009

STATUS

approved

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Last modified August 19 04:34 EDT 2019. Contains 326109 sequences. (Running on oeis4.)