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%I #22 Aug 09 2017 10:49:25
%S 6,10,12,14,15,20,21,22,24,26,28,33,34,35,38,39,40,44,46,48,51,52,55,
%T 56,57,58,62,65,68,69,74,76,77,80,82,85,86,87,88,91,92,93,94,95,96,
%U 104,106,111,112,115,116,118,119,122,123,124,129,133,134,136,141,142,143,145,146,148,152
%N Numbers with two distinct prime factors not divisible by a square larger than 4.
%H Charles R Greathouse IV, <a href="/A289558/b289558.txt">Table of n, a(n) for n = 1..10000</a>
%e 10 is in this sequence because A001221(10) = 2 and 10 is not divisible by a square greater than 4.
%t With[{nn = 10^4, r = 2}, Take[#, 67] &@ Union@ Flatten@ Table[Function[p, {p*2^Range[Log2[nn/p]], p DeleteCases[Prime@ Range[r, PrimePi[nn/p]], q_ /; q == p]}]@ Prime@ n, {n, r, PrimePi[nn/Prime[r]]}]] (* _Michael De Vlieger_, Jul 10 2017 *)
%o (PARI) list(lim)=my(v=List()); forprime(p=5,lim\3, forprime(q=3,min(lim\p,p-2), listput(v,p*q))); for(e=1,logint(lim\3,2), forprime(p=3,lim>>e, listput(v,p<<e))); Set(v) \\ _Charles R Greathouse IV_, Aug 09 2017
%Y The union of A046388 and A100368.
%Y Cf. A001221, A007814, A289184.
%K nonn,easy
%O 1,1
%A _Juri-Stepan Gerasimov_, Jul 08 2017
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