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A059404 Numbers n such that n/[largest power of squarefree kernel] is larger than 1. 9
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 n=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

n=440 is here because n=2.2.2.5.11, its sqf-kernel=110, quotient=4>1.

PROG

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

CROSSREFS

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

Sequence in context: A126706 A123711 A200511 * A242416 A177425 A182854

Adjacent sequences:  A059401 A059402 A059403 * A059405 A059406 A059407

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 18 2001

STATUS

approved

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Last modified May 23 23:53 EDT 2017. Contains 286937 sequences.