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A269300 Leading term in the sifting limit for Buchstab's iteration sieve. 1
2, 4, 4, 5, 1, 8, 5, 8, 6, 1, 3, 2, 4, 2, 5, 7, 4, 3, 8, 5, 1, 5, 6, 2, 8, 8, 0, 5, 7, 1, 8, 1, 0, 0, 7, 7, 8, 2, 4, 5, 7, 8, 2, 7, 6, 5, 3, 7, 5, 3, 7, 0, 8, 3, 1, 0, 9, 5, 6, 5, 8, 2, 7, 2, 0, 3, 8, 7, 0, 1, 6, 1, 6, 7, 8, 1, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
1,1
REFERENCES
George Greaves, Sieves in Number Theory (2001). See p. 4 and pp. 293-294.
LINKS
N. C. Ankeny and H. Onishi, The general sieve, Acta Arithmetica 10 (1964/1965), pp. 31-62. See theorems 2.4 and 2.5.
H. Iwaniec, J. van de Lune, and H. J. J. te Riele, The limits of Buchstab's iteration sieve, Indagationes Mathematicae 83:4 (1980), pp. 409-417.
FORMULA
2*exp(li(2)-gamma-1)/log(2)^2, where gamma is Euler's constant A001620.
EXAMPLE
2.44518586132425743851562880571810077824578276537537083109565827203870...
MATHEMATICA
RealDigits[2*Exp[LogIntegral[2] - EulerGamma - 1]/Log[2]^2, 10, 100][[1]] (* G. C. Greubel, Sep 07 2018 *)
PROG
(PARI) 2*exp(intnum(s=0, log(2), (exp(s)-1)/s)-log(log(2))-1)
(PARI) 2*exp(real(-eint1(-log(2)))-Euler-1)/log(2)^2
CROSSREFS
Cf. A001620.
Sequence in context: A009292 A009622 A232845 * A182215 A036443 A036437
KEYWORD
nonn,cons
AUTHOR
STATUS
approved

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Last modified May 29 04:03 EDT 2023. Contains 363029 sequences. (Running on oeis4.)