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A195007
Number of primes in the range (n*sqrt(n-1), (n+1)*sqrt(n)].
1
1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1, 1, 3, 2, 0, 1, 2, 1, 2, 1, 2, 1, 2, 2, 2, 1, 0, 3, 2, 1, 2, 1, 3, 2, 1, 1, 3, 0, 2, 2, 2, 1, 2, 2, 2, 1, 2, 2, 3, 1, 3, 1, 2, 2, 1, 2, 1, 1, 2, 3, 2, 2, 4, 1, 2, 2, 2, 3, 1, 2, 1, 2, 3, 2, 2, 1, 1
OFFSET
1,5
EXAMPLE
a(1)=1`because 1*sqrt(1-1)<(prime 2)<=(1+1)*sqrt(1),
a(2)=1 because 2*sqrt(2-1)<(prime 3)<=(2+1)*sqrt(2).
MATHEMATICA
Table[PrimePi[(n+1)*Sqrt[n]] - PrimePi[n*Sqrt[n-1]], {n, 100}] (* T. D. Noe, Sep 14 2011 *)
CROSSREFS
Sequence in context: A263000 A075774 A367760 * A276947 A178085 A078572
KEYWORD
nonn
AUTHOR
STATUS
approved