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A059404 Numbers k such that k/(largest power of squarefree kernel of k) is larger than 1. 25
12, 18, 20, 24, 28, 40, 44, 45, 48, 50, 52, 54, 56, 60, 63, 68, 72, 75, 76, 80, 84, 88, 90, 92, 96, 98, 99, 104, 108, 112, 116, 117, 120, 124, 126, 132, 135, 136, 140, 144, 147, 148, 150, 152, 153, 156, 160, 162, 164, 168, 171, 172, 175, 176, 180, 184, 188, 189 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A072774 (powers of squarefree numbers).

Also numbers k = p(1)^alpha(1)* ... * p(r)^alpha(r) such that RootMeanSquare(alpha(1), ..., alpha(r)) is not an integer. - Ctibor O. Zizka, Sep 19 2008

LINKS

Donald Alan Morrison, Table of n, a(n) for n = 1..10000

Donald Alan Morrison, Sage program

FORMULA

A062760(a(n)) > 1, i.e., a(n)/(A007947(a(n))^A051904(a(n)) = a(n)/A062759(n) > 1.

EXAMPLE

k=440 is in the sequence because k = 2*2*2*5*11, its squarefree kernel = 110, quotient = 4 > 1.

PROG

(PARI) is(n)=#Set(factor(n)[, 2])>1 \\ Charles R Greathouse IV, Sep 18 2015

CROSSREFS

Cf. A003557, A007947, A051904, A062759, A062760.

Sequence in context: A200511 A317711 A323055 * A303946 A242416 A317616

Adjacent sequences:  A059401 A059402 A059403 * A059405 A059406 A059407

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 18 2001

STATUS

approved

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Last modified March 19 00:12 EDT 2019. Contains 321306 sequences. (Running on oeis4.)