A305635 1 and odd numbers that are not perfect powers.

1, 3, 5, 7, 11, 13, 15, 17, 19, 21, 23, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 123, 127, 129, 131, 133, 135, 137

Offset: 1

Author

Gus Wiseman, Jun 07 2018

Keywords

• nonn

Crossrefs

Cf. A001597, A005117, A007916, A039956, A056911.

Cf. A305630, A305631, A305632, A305633, A305634.

Programs

Magma

[1] cat  [n : n in [3..200 by 2] | not IsPower(n) ]; // Vincenzo Librandi, Jul 06 2018

Mathematica

radQ[n_]:=Or[n==1,GCD@@FactorInteger[n][[All,2]]==1];
Select[Range[200],OddQ[#]&&radQ[#]&]

PARI

isok(n) = (n==1) || ((n % 2) && !ispower(n)); \\ Michel Marcus, Jun 08 2018