primecount References
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1. A. M. Legendre, Théorie des nombres, Third edition, Paris, 1830. Vol. 2, p. 65.
2. D. H. Lehmer, On the exact number of primes less than a given limit, Illinois J. Math. 3 (1959), pp. 381–388.
3. J. C. Lagarias, V. S. Miller, and A. M. Odlyzko, Computing pi(x): The Meissel-Lehmer method, Mathematics of Computation, 44 (1985), pp. 537–560.
4. M. Deleglise and J. Rivat, "Computing pi(x): The Meissel, Lehmer, Lagarias, Miller, Odlyzko Method", Mathematics of Computation, Volume 65, Number 213, 1996, pp 235–245.
5. Hans Riesel, Prime Numbers and Computer Methods for Factorization, 2nd ed., Birkhäuser, Boston, 1994. pp. 10-38.
6. Raymond Séroul, Programming for Mathematicians, Springer-Verlag, Berlin (2000), pp. 175-181.
7. Xavier Gourdon, Computation of pi(x) : improvements to the Meissel, Lehmer, Lagarias, Miller, Odllyzko, Deléglise and Rivat method, February 15, 2001.
8. R. Crandall and C. Pomerance, Prime numbers: a computational perspective, 2nd ed., Springer, New York, 2005. pp. 152-162.
9. Tomás Oliveira e Silva, Computing pi(x): the combinatorial method, Revista do DETUA, vol. 4, no. 6, March 2006, pp. 759-768.
10. Douglas B. Staple, The combinatorial algorithm for computing pi(x), Master of Science Thesis, Dalhousie University Halifax, Nova Scotia, August 2015.
11. Jan Büthe, An improved analytic method for calculating pi(x), Manuscripta Math. 151 (2016), no. 3-4, 329-352.