This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A101766 #20 Nov 12 2022 02:15:36
%S A101766 8,16,18,21,26,38,42,44,49,54,55,57,61,67,77,78,115,123,134,145,151,
%T A101766 154,202,218,249,286,349,403,498,539,647
%N A101766 Iccanobif semiprime indices: Indices of semiprime numbers in A014260.
%C A101766 This sequence also includes 790, 1161, 1347, 1418, 1595, 1761, and 2018. It might or might not include 769, 1394, 1795, 1983, 2093, 2178, but the required factoring proved rather difficult. There are no further terms below 2178. - _Lucas A. Brown_, Nov 12 2022
%H A101766 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A101766.py">A101766.py</a>.
%t A101766 nxt[{a_,b_}]:={b,IntegerReverse[a]+b}; Flatten[Position[NestList[nxt,{0,1},600][[All,1]],_?(PrimeOmega[#]==2&)]]-1 (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 04 2018 *)
%Y A101766 Cf. A001358, A001129, A014258, A014259, A014260, A101763, A101764, A101765.
%K A101766 nonn,base,hard,more
%O A101766 1,1
%A A101766 _Jonathan Vos Post_ and _Ray Chandler_, Dec 15 2004
%E A101766 Offset changed to 1 by _Jinyuan Wang_, Aug 01 2021
%E A101766 a(31) from _Lucas A. Brown_, Nov 12 2022