%I

%S 9,11,14,17,26,31,38,46,62,70,74,86,94,118,134,194,206,278,286,566,

%T 598,778,842,934,1006,1082,1214,1238,1546,1574,1726,1858,2018,2278,

%U 2474,2774,3142,3686

%N Indices n for which A209312(n)=2.

%C Many of these seem to be even semiprimes.

%C Is this sequence infinite, and if so, can someone exhibit an explicitely calculable subsequence?

%K nonn,more

%O 1,1

%A _M. F. Hasler_, Jan 19 2013