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Intersection of A126706 and A055932.
2

%I #22 Feb 01 2024 01:24:30

%S 12,18,24,36,48,54,60,72,90,96,108,120,144,150,162,180,192,216,240,

%T 270,288,300,324,360,384,420,432,450,480,486,540,576,600,630,648,720,

%U 750,768,810,840,864,900,960,972,1050,1080,1152,1200,1260,1296,1350,1440,1458

%N Intersection of A126706 and A055932.

%C Products m*P(i) of primorials P(i) = A002110(i) such that rad(m) | P(i), i > 1, m > 1, where rad(m) = A007947(m).

%H Michael De Vlieger, <a href="/A363814/b363814.txt">Table of n, a(n) for n = 1..10000</a>

%F Union of A056808 and A364710. - _Michael De Vlieger_, Jan 31 2024

%e Sequence contains terms k > 1 in {6 * A003586} since all are divisible by P(2) = 6 and by no prime q that does not divide 6. Therefore 12, 18, 24, etc. are in the sequence.

%e Sequence does not contain k > 1 in {10 * A003592} since such k are divisible by 5 but not 3. Hence, 20, 40, etc. are not in this sequence.

%e Sequence does not contain k > 1 in {15 * A003593} since such k are odd. Hence, 45, 135, etc. are not in this sequence, etc.

%t Select[Range[12, 1080, 2], And[AnyTrue[#2, # > 1 &], Length[#1] > 1, Union@ Differences@ PrimePi[#1] == {1}] & @@ Transpose@ FactorInteger[#] &]

%Y Cf. A002110, A007947, A013929, A024619, A055932, A056808, A126706, A364710.

%Y Cf. A003586, A003592, A003593.

%K nonn,easy

%O 1,1

%A _Michael De Vlieger_, Dec 18 2023