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Nonmultiples of 4 that have an even number of prime factors (with multiplicity).
5

%I #14 Dec 29 2022 09:09:21

%S 1,6,9,10,14,15,21,22,25,26,33,34,35,38,39,46,49,51,54,55,57,58,62,65,

%T 69,74,77,81,82,85,86,87,90,91,93,94,95,106,111,115,118,119,121,122,

%U 123,126,129,133,134,135,141,142,143,145,146,150,155,158,159,161,166,169,177,178,183,185,187,189

%N Nonmultiples of 4 that have an even number of prime factors (with multiplicity).

%C 1, and semiprimes other than 4, multiplied by a product of 0 or more odd semiprimes. - _Robert Israel_, Dec 28 2022

%F {k | A008836(k) > 0 and A010873(k) > 0}.

%p select(t -> numtheory:-bigomega(t)::even, [seq(seq(4*i+j, j=1..3),i=0..100)]); # _Robert Israel_, Dec 28 2022

%t Select[Range[200], And[LiouvilleLambda[#] > 0, ! Divisible[#, 4]] &] (* _Michael De Vlieger_, Dec 28 2022 *)

%o (PARI) isA359371(n) = A359370(n);

%Y Intersection of A028260 and A042968.

%Y Setwise difference A042968 \ A359373.

%Y Positions of positive terms in A358839.

%Y Cf. A001222, A008836, A010873, A046337 (subsequence), A166486, A359370 (characteristic function).

%K nonn

%O 1,2

%A _Antti Karttunen_, Dec 28 2022