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 A112879 #3 Mar 31 2012 13:22:04 %S A112879 3,107,206081,20894934252011 %N A112879 Define a(0)=3; then a(n)=k*a(n-1)^2-1=least prime first of twin primes. %C A112879 k sequence in A112880 %e A112879 12*3^2-1=107, 107 and 109 twin primes so a(1)=107 %e A112879 18*107^2-1=206081, 206081 and 206083 twin primes so a(2)=206081 %e A112879 a(3)=492*(18*(12*3^2-1)^2-1)^2-1 %e A112879 a(4)=702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1 %e A112879 a(5)=2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1 %e A112879 a(6)=2370*(2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1)^2-1 %e A112879 a(7)=130650*(2370*(2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1 %e A112879 a(8)=980910*(130650*(2370*(2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1 %e A112879 a(9)=5528418*(980910*(130650*(2370*(2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1 %e A112879 a(10)=21357012*(5528418*(980910*(130650*(2370*(2310*(702*(492*(18*(12*3^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1)^2-1 %Y A112879 Cf. A112880. %K A112879 hard,nonn %O A112879 0,1 %A A112879 _Pierre CAMI_, Oct 01 2005