login
A109507
Let x be a positive number, Lambda(d) = Moebius(d)*[log(x/d)]^2, f(m) = Sum_{d|m} Lambda(d), S(x) = Sum_{m <= x} f(m). Sequence gives nearest integer to S(n).
1
0, 1, 3, 7, 11, 15, 20, 25, 31, 35, 43, 46, 55, 60, 66, 71, 81, 85, 95, 100, 106, 112, 124, 127, 137, 143, 151, 156, 169, 171, 185, 192, 199, 205, 214, 217, 232, 238, 246, 250, 266, 268, 284, 290, 296, 302, 319, 323, 336, 340, 349, 354, 372, 376, 386, 390, 399
OFFSET
1,3
REFERENCES
T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, New York, 1976.
T. Nagell, "Introduction to Number Theory", Chelsea Pub., New York, 1964, Chap. VIII.
LINKS
J. J. O'Connor and E. F. Robertson, Atle Selberg.
Atle Selberg, An elementary proof of the prime number theorem for arithmetic progressions, Canad. J. Math., 2, (1949), 66-78.
Eric Weisstein's World of Mathematics, Selberg's Formula.
FORMULA
Selberg proved that S(x) = 2*x*log(x) + o(x*log(x)).
MATHEMATICA
lmbd[d_, x_] := MoebiusMu[d]*Log[x/d]^2; f[n_, x_] := Block[{d = Divisors[n]}, Plus @@ lmbd[d, x]]; s[x_] := Sum[f[n, x], {n, x}]; Table[ Floor[ s[n]], {n, 57}]
CROSSREFS
Cf. A109508.
Sequence in context: A310211 A310212 A310213 * A340699 A160802 A170888
KEYWORD
nonn
AUTHOR
STATUS
approved