A076403 Squarefree kernel of n-th perfect power.

1, 2, 2, 3, 2, 5, 3, 2, 6, 7, 2, 3, 10, 11, 5, 2, 6, 13, 14, 6, 15, 3, 2, 17, 6, 7, 19, 10, 21, 22, 2, 23, 6, 5, 26, 3, 14, 29, 30, 31, 10, 2, 33, 34, 35, 6, 11, 37, 38, 39, 10, 41, 6, 42, 43, 22, 15, 2, 46, 3, 13, 47, 6, 7, 10, 51, 26, 14, 53, 6, 55, 5, 14, 57, 58, 15, 59, 30, 61, 62

Offset

1,2

Comments

a(n) = A007947(A001597(n)).

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Perfect Powers.

Eric Weisstein's World of Mathematics, Squarefree Part.

Formula

a(n) = A007947(A025478(n)).

Mathematica

Prepend[Map[Times @@ FactorInteger[#][[All, 1]] &, DeleteCases[#, 0]], 1] &@ Table[If[Set[e, GCD @@ #[[All, -1]]] > 1, Power[n, 1/e], 0] &@ FactorInteger[n], {n, 4000}] (* Michael De Vlieger, Apr 25 2017 *)

Prog

(Haskell)
a076403 = a007947 . a025478 -- Reinhard Zumkeller, Mar 28 2014

Crossrefs

Cf. A025478.

Sequence in context: A076397 A254269 A264662 * A157987 A025478 A084371

Adjacent sequences: A076400 A076401 A076402 * A076404 A076405 A076406

Keyword

nonn

Author

Reinhard Zumkeller, Oct 09 2002

Status

approved