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A062770 n/[largest power of squarefree kernel] equals 1; perfect powers of sqf-kernels (or sqf-numbers). 19
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 46, 47, 49, 51, 53, 55, 57, 58, 59, 61, 62, 64, 65, 66, 67, 69, 70, 71, 73, 74, 77, 78, 79, 81, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

FORMULA

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

EXAMPLE

Primes, squarefree numbers and perfect powers are here.

MATHEMATICA

Rest@ Select[Range@ 100, Or[SquareFreeQ@ #, # == 1 || GCD @@ FactorInteger[#][[All, 2]] > 1] &] (* after Ant King at A001597, or *)

Select[Range[2, 100], Function[n, n/#^IntegerExponent[n, #] == 1 &@ Last@ Select[Divisors@ n, SquareFreeQ]]] (* Michael De Vlieger, Nov 02 2017 *)

PROG

(PARI) is(n)=ispower(n, , &n); issquarefree(n) && n>1 \\ Charles R Greathouse IV, Sep 18 2015

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

CROSSREFS

Cf. A062759, A062760, A007947, A003557, A051904, A005117, A001597.

Sequence in context: A085924 A242414 A072774 * A236510 A317710 A303554

Adjacent sequences:  A062767 A062768 A062769 * A062771 A062772 A062773

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 18 2001

EXTENSIONS

Offset corrected by Charles R Greathouse IV, Sep 18 2015

STATUS

approved

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Last modified October 16 23:30 EDT 2019. Contains 328103 sequences. (Running on oeis4.)