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A079553 Floor( d(n^2) / d(n) ), where d() = A000005. 3
1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 1, 2, 2, 2, 2, 1, 2, 2, 2, 1, 3, 1, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 2, 2, 1, 3, 1, 2, 2, 1, 2, 3, 1, 2, 2, 3, 1, 2, 1, 2, 2, 2, 2, 3, 1, 2, 1, 2, 1, 3, 2, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 1, 3, 1, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

COMMENTS

This sequence and A087802 first differ at term 144: a(144)=3 and A087802(144)=2. This sequence and A064372 first differ at term 64: a(64)=1 and A064372(64)=2. The next difference doesn't appear until a(144)=3 and A064372(144)=2. - Rick L. Shepherd, Mar 07 2004

Differs from A001221 at n=1, 144, 180, 210, 216 etc. - R. J. Mathar, Sep 19 2008

REFERENCES

D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, p. 41.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..5000

MATHEMATICA

Table[Floor[DivisorSigma[0, n^2]/DivisorSigma[0, n]], {n, 1, 50}] (* G. C. Greubel, May 14 2017 *)

PROG

(PARI) A079553(n)=floor(numdiv(n^2)/numdiv(n))

CROSSREFS

Sequence in context: A231813 A158210 A087802 * A001221 A064372 A096825

Adjacent sequences:  A079550 A079551 A079552 * A079554 A079555 A079556

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 24 2003

STATUS

approved

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Last modified December 16 01:36 EST 2017. Contains 296063 sequences.