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%I #4 Jan 01 2015 12:16:44
%S 9,21,33,93,111,129,177,213,237,267,309,321,381,411,519,579,597,633,
%T 687,699,723,753,789,831,879,921,951,1047,1149,1257,1299,1317,1347,
%U 1401,1461,1641,1713,1731,1779,1797,1821,1983,2031,2049,2103,2181,2427,2469
%N If, for some m, A098550(m-2) is a prime p and A098550(m) = 3p, add 3p to the sequence.
%C A subsequence of A251544 (and of course of A098550).
%Y Cf. A098550, A251544, A253053, A253054.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Jan 01 2015