%I #13 Sep 05 2020 20:57:34
%S 4,46,6,62,21,14,49,9,91,15,51,106,65,55,57,74,403,33,34,407,77,703,
%T 35,58,82,22,25,501,111,115,502,26,69,93,38,85,505,511,118,86,611,119,
%U 94,411,121,122,201,123,39,95,514,413,301,129,901,133,302,202,203,303,305
%N a(1)=4, then a(n) is the smallest semiprime not occurring earlier, not ending with zero and starting with the last digit of a(n-1).
%H David A. Corneth, <a href="/A119729/b119729.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Zak Seidov)
%Y Cf. A000030, A001358, A010879.
%K nonn,base,easy
%O 1,1
%A _Jonathan Vos Post_, Jun 14 2006
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