A102181 Iccanobirt semiprime indices (11 of 15): Indices of semiprime numbers in A102121.
5, 11, 12, 17, 18, 37, 38, 43, 44, 45, 55, 61, 70, 93, 103, 110, 120, 129, 174, 198, 241, 245, 277, 303, 342, 381, 393, 552, 590, 657, 708
Offset: 1
Programs
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Mathematica
nxt[{a_,b_,c_}]:={b,c,IntegerReverse[c+IntegerReverse[b]+IntegerReverse[a]]}; Flatten[ Position[NestList[nxt,{0,0,1},800][[;;,1]],?(PrimeOmega[#]==2&)]-1] (* _Harvey P. Dale, Mar 23 2023 *)
Extensions
Offset changed to 1 and a(21)-a(31) from Jinyuan Wang, Aug 14 2021