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A053822 Dirichlet inverse of sigma_2 function (A001157). 2
1, -5, -10, 4, -26, 50, -50, 0, 9, 130, -122, -40, -170, 250, 260, 0, -290, -45, -362, -104, 500, 610, -530, 0, 25, 850, 0, -200, -842, -1300, -962, 0, 1220, 1450, 1300, 36, -1370, 1810, 1700, 0, -1682, -2500, -1850, -488, -234, 2650, -2210, 0, 49, -125, 2900, -680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

sigma_2(n) is the sum of the squares of the divisors of n (A001157).

REFERENCES

T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, 1976, page 39.

LINKS

Table of n, a(n) for n=1..52.

FORMULA

Dirichlet g.f.: 1/(zeta(x)zeta(x-2))

Multiplicative with a(p^1) = -1-p^2, a(p^2) = p^2, a(p^e) = 0 for e>=3. Mitch Harris Jun 27, 2005.

CROSSREFS

Sequence in context: A084341 A054513 A066200 * A137404 A110643 A010721

Adjacent sequences:  A053819 A053820 A053821 * A053823 A053824 A053825

KEYWORD

sign,mult

AUTHOR

N. J. A. Sloane, Apr 08 2000

STATUS

approved

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Last modified May 21 07:04 EDT 2013. Contains 225477 sequences.