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A083535
A version of the Chebyshev function theta(n): a(n) = ceiling(Sum_{primes p <= n } log(p)).
4
0, 1, 2, 2, 4, 4, 6, 6, 6, 6, 8, 8, 11, 11, 11, 11, 14, 14, 17, 17, 17, 17, 20, 20, 20, 20, 20, 20, 23, 23, 27, 27, 27, 27, 27, 27, 30, 30, 30, 30, 34, 34, 38, 38, 38, 38, 41, 41, 41, 41, 41, 41, 45, 45, 45, 45, 45, 45, 50, 50, 54, 54, 54, 54, 54, 54, 58, 58, 58, 58, 62, 62, 66, 66, 66, 66
OFFSET
1,3
COMMENTS
See A035158, which is the main entry for this function.
The old entry with this sequence number was a duplicate of A083235.
FORMULA
a(n) ~ n by the prime number theorem. - Charles R Greathouse IV, Aug 02 2012
CROSSREFS
Sequence in context: A057144 A198332 A080606 * A250983 A070320 A124195
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 02 2008
STATUS
approved