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 A102142 #12 Apr 10 2020 15:59:58 %S A102142 4,6,7,12,19,30,37,67,93,109,297,341,602,1377,1745,1972,4208,7942, %T A102142 9572,10409,11927,12707,13460,33803 %N A102142 Iccanobirt prime indices (12 of 15): Indices of prime numbers in A102122. %C A102142 No more terms through 5000. %C A102142 a(25) > 50000. - _Robert Price_, Nov 10 2018 %F A102142 A102122(a(n)) = A102162(n). %t A102142 a[n_] := a[n] = %t A102142 IntegerReverse[IntegerReverse[a[n - 1]] + a[n - 2] + a[n - 3]]; %t A102142 a[0] = 0; a[1] = 0; a[2] = 1; %t A102142 Select[Range[0, 5000], PrimeQ[a[#]] &] (* _Robert Price_, Apr 10 2020 *) %Y A102142 Cf. A000040, A102122, A102131-A102145. %K A102142 nonn,more,base %O A102142 1,1 %A A102142 _Jonathan Vos Post_ and _Ray Chandler_, Dec 31 2004 %E A102142 a(18)-a(24) from _Robert Price_, Nov 10 2018