A367018 -id:A367018 - cp's OEIS frontend

A367455 Numbers not divisible by 6 that are neither squarefree nor prime powers.

20, 28, 40, 44, 45, 50, 52, 56, 63, 68, 75, 76, 80, 88, 92, 98, 99, 100, 104, 112, 116, 117, 124, 135, 136, 140, 147, 148, 152, 153, 160, 164, 171, 172, 175, 176, 184, 188, 189, 196, 200, 207, 208, 212, 220, 224, 225, 232, 236, 242, 244, 245, 248, 250, 260, 261

Offset: 1

Michael De Vlieger, Jan 15 2024

A364997 is a proper subset.

The asymptotic density of this sequence is 1/6 - 1/(2*Pi^2). - Amiram Eldar, Jan 20 2024

Michael De Vlieger, Table of n, a(n) for n = 1..10000

Cf. A001221, A001222, A047253, A053669, A119288, A126706, A364997, A365710, A367018.

Select[Range[261], And[Nor[SquareFreeQ[#], PrimePowerQ[#]], Mod[#, 6] != 0] &]

Intersection of A047253 and A126706.
Let p = A119288(k) and q = A053669(k) for k in A126706. Various definitions of this sequence:
{a(n)} = { k : Omega(k) > omega(k) > 1, p > q }.
{a(n)} = { k : Omega(k) > omega(k) > 1, k mod 6 != 0 }.
{a(n)} = { k = mx : x in A367018, rad(m) | x, m > 1. }.

cp's OEIS Frontend

A367455 Numbers not divisible by 6 that are neither squarefree nor prime powers.

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