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A073752 Greatest common divisor of n/spf(n) and n/gpf(n) where spf(n) is the smallest and gpf(n) is the greatest prime factor of n (see A020639, A006530). 3
1, 1, 1, 2, 1, 1, 1, 4, 3, 1, 1, 2, 1, 1, 1, 8, 1, 3, 1, 2, 1, 1, 1, 4, 5, 1, 9, 2, 1, 3, 1, 16, 1, 1, 1, 6, 1, 1, 1, 4, 1, 3, 1, 2, 3, 1, 1, 8, 7, 5, 1, 2, 1, 9, 1, 4, 1, 1, 1, 6, 1, 1, 3, 32, 1, 3, 1, 2, 1, 5, 1, 12, 1, 1, 5, 2, 1, 3, 1, 8, 27, 1, 1, 6, 1, 1, 1, 4, 1, 9, 1, 2, 1, 1, 1, 16, 1, 7, 3, 10, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

a(n) = if n=p^k (p prime, k>0) then p^(k-1) else n/(spf(n)*gpf(n)).

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = GCD(A032742(n), A052126(n)).

MATHEMATICA

gc[n_]:=Module[{fi=Transpose[FactorInteger[n]][[1]]}, GCD[n/First[fi], n/Last[ fi]]]; Array[gc, 110] (* Harvey P. Dale, Jun 17 2012 *)

CROSSREFS

Cf. A000961, A066048.

A073753(n) = a(a(n)).

Sequence in context: A000189 A000190 A003557 * A128708 A087653 A295666

Adjacent sequences:  A073749 A073750 A073751 * A073753 A073754 A073755

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Aug 07 2002

STATUS

approved

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Last modified September 22 08:23 EDT 2018. Contains 315270 sequences. (Running on oeis4.)