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%I #7 Aug 07 2023 15:44:07
%S 6,10,14,15,20,21,22,26,28,33,34,35,38,39,44,46,51,52,55,57,58,62,65,
%T 68,69,74,76,77,82,85,86,87,88,91,92,93,94,95,99,104,106,111,115,116,
%U 117,118,119,122,123,124,129,133,134,136,141,142,143,145,146,148,152,153
%N Numbers n having exactly 2 distinct prime factors, the largest of which is greater than or equal to sqrt(n) (i.e., sqrt(n)-rough numbers with exactly 2 distinct prime factors).
%e 20 is in the sequence because it has 2 distinct prime factors (2 and 5) and 5 > sqrt(20).
%p with(numtheory): a:=proc(n) if nops(factorset(n))=2 and factorset(n)[2]^2>=n then n else fi end: seq(a(n),n=1..170);
%t tdpfQ[n_]:=Module[{fi=FactorInteger[n]},Length[fi]==2&&fi[[2,1]]>Sqrt[n]]; Select[Range[ 200],tdpfQ] (* _Harvey P. Dale_, Aug 07 2023 *)
%Y Cf. A115957, A115958, A115959, A115960, A115961.
%K nonn
%O 1,1
%A _Emeric Deutsch_, Feb 02 2006
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