A359157 - OEIS

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A359157

Numbers whose odd part is squarefree and the number of prime factors (with multiplicity) is even.

1, 4, 6, 10, 14, 15, 16, 21, 22, 24, 26, 33, 34, 35, 38, 39, 40, 46, 51, 55, 56, 57, 58, 60, 62, 64, 65, 69, 74, 77, 82, 84, 85, 86, 87, 88, 91, 93, 94, 95, 96, 104, 106, 111, 115, 118, 119, 122, 123, 129, 132, 133, 134, 136, 140, 141, 142, 143, 145, 146, 152, 155, 156, 158, 159, 160, 161, 166, 177

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OFFSET

1,2

COMMENTS

Numbers k such that A355689(k) > 0, where A355689 is the Dirichlet inverse of A166486, characteristic function of numbers that are not multiples of 4.

The asymptotic density of this sequence is 4/Pi^2 (A185199). - Amiram Eldar, Jan 18 2023

LINKS

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

MATHEMATICA

Select[Range[200], EvenQ[PrimeOmega[#]] && SquareFreeQ[#/2^IntegerExponent[#, 2]] &] (* Amiram Eldar, Jan 18 2023 *)

PROG

(PARI) isA359157(n) = A359156(n);

CROSSREFS

Intersection of A028260 and A122132.

Setwise difference A122132 \ A359159.

Positions of positive terms in A355689.

Cf. A166486, A185199, A359156 (characteristic function).