OFFSET
1,1
COMMENTS
2^n/log(2^n) is an approximation to the number of primes < 2^n.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
FORMULA
MATHEMATICA
Floor[2^#/Log[2^#]]&/@Range[40] (* Harvey P. Dale, Mar 11 2013 *)
PROG
(PARI) g(n) = for(x=1, n, y=floor(2^x/log(2^x)); print1(y", "))
(PARI) a(n) = 2^n\log(2^n); \\ Michel Marcus, Feb 24 2021
(Magma)
A141602:= func< n | Floor(2^n/(n*Log(2))) >;
[A141602(n): n in [1..40]]; // G. C. Greubel, Sep 21 2024
(SageMath)
def A141602(n): return int(2^n/(n*log(2)))
[A141602(n) for n in range(1, 41)] # G. C. Greubel, Sep 21 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Cino Hilliard, Aug 21 2008
STATUS
approved