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Numbers k such that bigomega(k) and A064547(k) are both even, where A064547 is the count of 1-bits in the exponents of the prime factorization of n, and bigomega is the number of prime factors of n (with multiplicity).
5

%I #7 Jul 14 2024 15:16:35

%S 1,6,10,14,15,21,22,26,33,34,35,36,38,39,46,51,55,57,58,62,64,65,69,

%T 74,77,82,85,86,87,91,93,94,95,100,106,111,115,118,119,122,123,129,

%U 133,134,141,142,143,144,145,146,155,158,159,161,166,177,178,183,185,187,194,196,201,202,203,205,206,209,210,213

%N Numbers k such that bigomega(k) and A064547(k) are both even, where A064547 is the count of 1-bits in the exponents of the prime factorization of n, and bigomega is the number of prime factors of n (with multiplicity).

%H Antti Karttunen, <a href="/A374472/b374472.txt">Table of n, a(n) for n = 1..12000</a>

%o (PARI) isA374472 = A374471;

%Y Cf. A001222, A064547, A374471 (characteristic function), A374473 (complement).

%Y Indices of even terms in A374470.

%Y Intersection of A000379 and A028260.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jul 14 2024