A136012 - OEIS

%I #3 Mar 31 2012 10:32:41

%S 14,15,20,21,22,33,34,35,36,38,39,40,44,45,46,50,51,52,54,55,56,57,58,

%T 62,63,68,69,74,75,76,77,85,86,87,88,91,92,93,94,95,96,98,99,100,111,

%U 112,115,116,117,118,119,122,123,124,133,134,135,136,141,142,143,144

%N Numbers n in any run of two or more numbers each having exactly two distinct prime divisors.

%e a(3) to a(5), 20 to 22, are a run of 3 consecutive numbers each having exactly 2 distinct prime divisors.

%Y Cf. A001221, A064709.

%K easy,nonn

%O 1,1

%A _Enoch Haga_, Dec 09 2007

%E Corrected and edited by _R. J. Mathar_, Dec 12 2007