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A076292 Perfect powers with squarefree root. 2
1, 4, 8, 9, 16, 25, 27, 32, 36, 49, 64, 81, 100, 121, 125, 128, 169, 196, 216, 225, 243, 256, 289, 343, 361, 441, 484, 512, 529, 625, 676, 729, 841, 900, 961, 1000, 1024, 1089, 1156, 1225, 1296, 1331, 1369, 1444, 1521, 1681, 1764, 1849, 2048, 2116, 2187 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
A025478(a(n)) = A007947(a(n)).
EXAMPLE
A001597(17) = 144 = (3*2^2)^2 is not a term.
MATHEMATICA
q[n_] := n == 1 || Length[(u = Union[FactorInteger[n][[;; , 2]]])] == 1 && u[[1]] > 1; Select[Range[2000], q] (* Amiram Eldar, Jan 01 2022 *)
PROG
(PARI) is(n)=n==1 || (ispower(n, , &n) && issquarefree(n)) \\ Charles R Greathouse IV, Oct 16 2015
CROSSREFS
Sequence in context: A001597 A359493 A072777 * A090516 A090515 A075309
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Nov 06 2002
STATUS
approved

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Last modified March 19 06:47 EDT 2024. Contains 370953 sequences. (Running on oeis4.)