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A066638 Smallest power of a squarefree number that is a multiple of n. 9
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 36, 13, 14, 15, 16, 17, 36, 19, 100, 21, 22, 23, 216, 25, 26, 27, 196, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 1000, 41, 42, 43, 484, 225, 46, 47, 1296, 49, 100, 51, 676, 53, 216, 55, 2744, 57, 58, 59 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = rad(n)^mpe(n), (rad=A007947, mpe=A051903).
a(n) = A066636(n) * n. - Amiram Eldar, Sep 15 2023
EXAMPLE
a(40)=10^3 > 40 > 10=rad(40).
MATHEMATICA
rad[n_] := Times @@ First /@ FactorInteger[n]; mpe[n_] := Max @@ Last /@ FactorInteger[n]; mpe[1] = 0; a[n_] := rad[n]^mpe[n]; Table[a[n], {n, 1, 59}] (* Jean-François Alcover, Mar 27 2013 *)
PROG
(PARI) a(n)=if(n==1, return(1)); my(f=factor(n)); prod(i=1, #f~, f[i, 1])^ vecmax(f[, 2]) \\ Charles R Greathouse IV, Aug 21 2013
(Haskell)
a066638 n = a007947 n ^ a051903 n -- Reinhard Zumkeller, Jun 17 2015
CROSSREFS
Sequence in context: A300819 A161949 A004851 * A285769 A219209 A223474
KEYWORD
nonn,nice
AUTHOR
Reinhard Zumkeller, Jan 09 2002
STATUS
approved

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Last modified April 23 18:16 EDT 2024. Contains 371916 sequences. (Running on oeis4.)