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A078599 Product of squarefree divisors of n. 5
1, 2, 3, 2, 5, 36, 7, 2, 3, 100, 11, 36, 13, 196, 225, 2, 17, 36, 19, 100, 441, 484, 23, 36, 5, 676, 3, 196, 29, 810000, 31, 2, 1089, 1156, 1225, 36, 37, 1444, 1521, 100, 41, 3111696, 43, 484, 225, 2116, 47, 36, 7, 100, 2601, 676, 53, 36, 3025, 196, 3249, 3364 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n)=a(rad(n)), where rad(n) is the squarefree kernel of n; a(A006881(n))=A006881(n)^2; a(A000040(n))=A000040(n).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A007955(A007947(n)) - T. D. Noe, Jul 08 2008

EXAMPLE

Divisors of n=20: {1,2,4,5,10,20}, 4=2^2 and 20=5*2^2, therefore a(20)=1*2*5*10=100.

MATHEMATICA

Table[Times@@Select[Divisors[n], SquareFreeQ], {n, 60}] (* Harvey P. Dale, Jul 03 2019 *)

CROSSREFS

Cf. A005117, A007947, A034444.

Sequence in context: A037279 A163591 A085307 * A183103 A183105 A316608

Adjacent sequences:  A078596 A078597 A078598 * A078600 A078601 A078602

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Dec 09 2002

STATUS

approved

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Last modified November 15 08:37 EST 2019. Contains 329144 sequences. (Running on oeis4.)