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A035158 A version of the Chebyshev function theta(n): a(n) = floor(Sum_{primes p <= n } log(p)). 3
0, 0, 1, 1, 3, 3, 5, 5, 5, 5, 7, 7, 10, 10, 10, 10, 13, 13, 16, 16, 16, 16, 19, 19, 19, 19, 19, 19, 22, 22, 26, 26, 26, 26, 26, 26, 29, 29, 29, 29, 33, 33, 37, 37, 37, 37, 40, 40, 40, 40, 40, 40, 44, 44, 44, 44, 44, 44, 49, 49, 53, 53, 53, 53, 53, 53, 57, 57, 57, 57, 61, 61, 65, 65, 65, 65 (list; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

The old entry with this sequence number was a duplicate of A002325.

REFERENCES

G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 5th ed., Oxford Univ. Press, 1979, see Chap. 22.

D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section VII.35. (For inequalities, etc.)

J. Barkley Rosser and Lowell Schoenfeld, Approximate formulas for some functions of prime numbers, Ill. Journ. Math. 6 (1962) 64-94.

J. Barkley Rosser and Lowell Schoenfeld, Sharper bounds for the Chebyshev functions theta(x) and psi(x), Math. Comp. 29 (1975), no. 129, 243-269.

Schoenfeld, Lowell, Corrigendum: "Sharper bounds for the Chebyshev functions theta(x) and psi(x). II" (Math. Comput. 30 (1976), number 134, 337-360). Math. Comp. 30 (1976), number 136, 900.

LINKS

J. Barkley Rosser and Lowell Schoenfeld, Approximate formulas for some functions of prime numbers (scan of some key pages from an ancient annotated photocopy)

MAPLE

(Maple for A035158, A057872, A083535:)

Digits:=2000;

tf:=[]; tr:=[]; tc:=[];

for n from 1 to 120 do

t2:=0;

j:=pi(n);

for i from 1 to j do t2:=t2+log(ithprime(i)); od;

tf:=[op(tf), floor(evalf(t2))];

tr:=[op(tr), round(evalf(t2))];

tc:=[op(tc), ceil(evalf(t2))];

od:

CROSSREFS

Cf. A057872, A083535.

Sequence in context: A129972 A130829 A196386 * A196172 A123313 A131507

Adjacent sequences:  A035155 A035156 A035157 * A035159 A035160 A035161

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Oct 02 2008

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Last modified February 17 09:17 EST 2012. Contains 206009 sequences.