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A073753 a(n) = A073752(A073752(n)), where A073752(n) = gcd(n/spf(n), n/gpf(n)), with spf(n) as the smallest and gpf(n) as the greatest prime factor of n (see A020639, A006530). 3
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 1, 8, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 1, 1, 16, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 4, 9, 1, 1, 1, 1, 1, 1, 2, 1, 3, 1, 1, 1, 1, 1, 8, 1, 1, 1, 1, 1, 1, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,8
COMMENTS
a(n) = A062378(n) for n<90, but a(90)=3 <> A062378(90)=1.
LINKS
FORMULA
a(n) = A073752(A073752(n)).
MATHEMATICA
A073752[n_] := With[{f = FactorInteger[n][[All, 1]]}, GCD[n/f[[1]], n/f[[-1]]]];
a[n_] := A073752[A073752[n]];
Array[a, 100] (* Jean-François Alcover, Dec 03 2021 *)
CROSSREFS
Differs from A062378 for the first time at n=90.
Sequence in context: A204133 A342017 A062378 * A290602 A255404 A078090
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 07 2002
EXTENSIONS
Name edited by Antti Karttunen, Sep 23 2017
STATUS
approved

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Last modified March 19 01:34 EDT 2024. Contains 370952 sequences. (Running on oeis4.)