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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
OFFSET
1,1
COMMENTS
The corresponding sequence for primes is A144264, and the ratio is given by sequences A161621/A161622.
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 * A331556 A188358 A228218
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