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A090395 Denominator of d(n)/n, where d(n) (A000005) is the number of divisors of n. 5
1, 1, 3, 4, 5, 3, 7, 2, 3, 5, 11, 2, 13, 7, 15, 16, 17, 3, 19, 10, 21, 11, 23, 3, 25, 13, 27, 14, 29, 15, 31, 16, 33, 17, 35, 4, 37, 19, 39, 5, 41, 21, 43, 22, 15, 23, 47, 24, 49, 25, 51, 26, 53, 27, 55, 7, 57, 29, 59, 5, 61, 31, 21, 64, 65, 33, 67, 34, 69, 35, 71, 6, 73, 37, 25, 38 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

The first occurrence of k is given in A091895.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

EXAMPLE

a(6)=3 because the number of divisors of 6 is 4 and 4 divided by 6 equals 2/3, which has 3 as its denominator.

MAPLE

with(numtheory): seq(denom(tau(n)/n), n=1..75) ; # Zerinvary Lajos, Jun 04 2008

MATHEMATICA

Table[ Denominator[ DivisorSigma[0, n]/n], {n, 1, 80}] (* Robert G. Wilson v, Feb 04 2004 *)

PROG

(PARI) A090395(n) = denominator(numdiv(n)/n); \\ Antti Karttunen, Sep 25 2018

CROSSREFS

Cf. A000005, A090387 (numerators).

Sequence in context: A298734 A137926 A218342 * A168485 A276737 A270027

Adjacent sequences:  A090392 A090393 A090394 * A090396 A090397 A090398

KEYWORD

easy,frac,nonn

AUTHOR

Ivan_E_Mayle(AT)a_provider.com, Jan 31 2004

EXTENSIONS

More terms from Robert G. Wilson v, Feb 04 2004

STATUS

approved

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Last modified January 18 17:18 EST 2022. Contains 350455 sequences. (Running on oeis4.)