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A058208 Floor(6*n*sqrt(n)/Pi^2) - sigma(n), where sigma(n) is the sum of the divisors of n (A000203). 4
-1, -2, -1, -3, 0, -4, 3, -2, 3, 1, 10, -3, 14, 7, 11, 7, 24, 7, 30, 12, 26, 26, 43, 11, 44, 38, 45, 34, 64, 27, 72, 47, 67, 66, 77, 40, 98, 82, 92, 63, 117, 69, 127, 93, 105, 117, 147, 78, 151, 121, 149, 129, 180, 121, 175, 134, 181, 178, 215, 114, 227, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Always > 0 for n > 12.

REFERENCES

D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section III.1.1.b.

LINKS

Table of n, a(n) for n=1..62.

PROG

(PARI) a(n)=6*n*sqrt(n)\Pi^2 - sigma(n) \\ Charles R Greathouse IV, Feb 14 2013

CROSSREFS

Cf. A000203, A057641, A055682.

Sequence in context: A030109 A208571 A264520 * A070817 A231347 A180988

Adjacent sequences:  A058205 A058206 A058207 * A058209 A058210 A058211

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Nov 29 2000

STATUS

approved

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Last modified August 18 14:09 EDT 2017. Contains 290720 sequences.