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 A104132 #20 May 23 2020 06:54:59
%S A104132 13,71,1806113,2699538733,
%T A104132 568972471024107865287021434301977158534824481,
%U A104132 5926187589691497537793497756719
%N A104132 Largest prime factor of pip(n)^pip(n)-1 where pip(n) is the n-th prime-indexed prime.
%H A104132 Amiram Eldar, <a href="/A104132/b104132.txt">Table of n, a(n) for n = 1..10</a>
%F A104132 a(n) = A006530(A048861(A006450(n))). - _Amiram Eldar_, May 23 2020
%t A104132 lpf[n_]:=Module[{p=Prime[Prime[n]]},FactorInteger[p^p-1][[-1,1]]]; Array[lpf,6] (* _Harvey P. Dale_, Nov 09 2017 *)
%o A104132 (PARI) piptopipm1(n) = { local(x, y); for(x=1, n, y=pip(x)^pip(x)-1; print1(bdiv(y)", "); ) }
%o A104132 pip(n) = { return(prime(prime(n))) }
%o A104132 bdiv(n) = { local(x); x=ifactor(n); return(x[length(x)]) }
%o A104132 ifactor(n, m=0) = { local(f, j, k, flist); flist=[]; f=Vec(factor(n, m)); for(j=1, length(f[1]), for(k = 1, f[2][j], flist = concat(flist, f[1][j]) ); ); return(flist) }
%Y A104132 Cf. A006450, A006530, A006486, A048861, A104131, A214812.
%K A104132 nonn,less
%O A104132 1,1
%A A104132 _Cino Hilliard_, Mar 06 2005
%E A104132 a(6) corrected by _Harvey P. Dale_, Nov 09 2017