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A100367 Even numbers with two prime factors, not counting multiplicity. 14

%I #25 Mar 15 2024 07:24:36

%S 6,10,12,14,18,20,22,24,26,28,34,36,38,40,44,46,48,50,52,54,56,58,62,

%T 68,72,74,76,80,82,86,88,92,94,96,98,100,104,106,108,112,116,118,122,

%U 124,134,136,142,144,146,148,152,158,160,162,164,166,172,176,178,184,188

%N Even numbers with two prime factors, not counting multiplicity.

%C This is a proper subset of A098902. E.g., 210 is not here, but it is there.

%C Numbers of the form 2^k*p^h where k > 0, h > 0, and p is an odd prime. [corrected by _Lei Zhou_, Oct 29 2018]

%H Michael De Vlieger, <a href="/A100367/b100367.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[2, 200, 2], PrimeNu@ # == 2 &] (* _Michael De Vlieger_, Oct 31 2018 *)

%o (PARI) isok(n) = !(n%2) && (omega(n) == 2); \\ _Michel Marcus_, Feb 02 2018

%Y Cf. A001221.

%Y Intersection of A007774 and A098902.

%Y The even terms of A336101.

%Y A100368 is a subsequence.

%K nonn

%O 1,1

%A _Labos Elemer_, Nov 22 2004

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)