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A016040
Integer part of Chebyshev's theta function: floor( log(Product_{k=1..n} prime(k)) ).
6
0, 1, 3, 5, 7, 10, 13, 16, 19, 22, 26, 29, 33, 37, 40, 44, 49, 53, 57, 61, 65, 70, 74, 79, 83, 88, 92, 97, 102, 107, 111, 116, 121, 126, 131, 136, 141, 146, 151, 157, 162, 167, 172, 177, 183, 188, 193, 199, 204, 210, 215, 221, 226, 232, 237, 243, 248
OFFSET
1,3
LINKS
J. W. Sander, A story of binomial coefficients and primes, Amer. Math. Monthly 102 (1995), 802-807.
FORMULA
a(n) = A000195(A002110(n)).
a(n) ~ n log n by the prime number theorem. - Charles R Greathouse IV, Dec 11 2008
MATHEMATICA
Table[Floor[N[Sum[Log[Prime[x]], {x, 1, n}]]], {n, 1, 1000}] (* Artur Jasinski, Jan 23 2007 *)
CROSSREFS
Cf. A035158.
Sequence in context: A079511 A092757 A062430 * A003070 A036604 A001768
KEYWORD
nonn
EXTENSIONS
New name from Charles R Greathouse IV, Dec 11 2008
STATUS
approved