A076333 Squarefree kernels of nonsquarefree numbers.

2, 2, 3, 6, 2, 6, 10, 6, 5, 3, 14, 2, 6, 10, 22, 15, 6, 7, 10, 26, 6, 14, 30, 21, 2, 34, 6, 15, 38, 10, 3, 42, 22, 30, 46, 6, 14, 33, 10, 26, 6, 14, 58, 39, 30, 11, 62, 5, 42, 2, 66, 15, 34, 70, 6, 21, 74, 30, 38, 51, 78, 10, 6, 82, 42, 13, 57, 86, 35, 22, 30, 46, 94, 21, 6, 14, 66

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Formula

a(n) = A007947(A013929(n)).

Sum_{k=1..n} a(k) ~ c * n^2 / 2, where c = (A065463 - 6/Pi^2)/(1 - 6/Pi^2)^2 = 0.627858264532... . - Amiram Eldar, Dec 09 2023

Mathematica

f[n_] := If[(r = Times @@ FactorInteger[n][[;; , 1]]) < n, r , 0]; Select[f /@ Range[200], # > 0 &] (* Amiram Eldar, Sep 07 2020 *)

Crossrefs

Cf. A007947, A013929.

Cf. A059956, A065463.

Sequence in context: A207621 A209157 A284785 * A015051 A362199 A260389

Adjacent sequences: A076330 A076331 A076332 * A076334 A076335 A076336

Keyword

nonn

Author

Reinhard Zumkeller, Nov 06 2002

Status

approved