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A228065
Difference of consecutive integers nearest to (10^n)/log(10^n) (A057834).
3
4, 18, 123, 941, 7600, 63696, 548039, 4808260, 42826261, 386039540, 3513837172, 32243075171, 297881471562, 2768030763779, 25850862018051, 242481085729315, 2283239371770773, 21572797793887019, 204448571890127322, 1942896366409284492
OFFSET
1,1
COMMENTS
This sequence gives an approximation of the number of primes with n digits (A006879); see A228066.
Note that A057834(n) = (10^n)/log(10^n) is not defined for n=0. Its value is set arbitrarily to 0.
LINKS
Eric Weisstein's World of Mathematics, Prime Counting Function.
FORMULA
a(n) = A057834(n) - A057834(n-1).
EXAMPLE
For n = 1, A057834(1) - A057834(0) = 4-0 = 4.
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Pletser, Aug 06 2013
STATUS
approved