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%I #4 Dec 26 2014 17:34:47
%S 4,6,9,10,14,15,21,22,26,33,34,38,39,46,51,57,58,62,69,74,82,86,87,93,
%T 94,106,111,118,122,123,129,134,141,142,146,158,159,166,177,178,183,
%U 194,201,202,206,213,214,218,219,226,237,249,254,262,267,274,278
%N Semiprimes with smallest factor <= 3.
%C A253046(a(n)) != a(n).
%H Reinhard Zumkeller, <a href="/A253106/b253106.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o a253106 n = a253106_list !! (n-1)
%o a253106_list = filter f [1..] where
%o f x = p <= 3 && a010051' (div x p) == 1 where p = a020639 x
%Y Cf. Union of A001748 and A100484, A020639, A010051, A001358, A171156, A253046.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Dec 26 2014