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 A066617 #12 Dec 15 2017 17:35:48
%S A066617 4,8,24,32,128,384,1152,3584,5120,6144,8192,73728,131072,524288,
%T A066617 5505024,10616832,14680064,18874368,109051904,169869312,654311424,
%U A066617 738197504,2147483648,21474836480,51539607552,824633720832,3710851743744
%N A066617 Composites of form prime+1 containing a record number of prime factors.
%C A066617 The sequence contains all numbers of the form (Mersenne Prime)+1 as a subset. - _Hugo Pfoertner_, Sep 10 2004
%e A066617 a(19)=109051904=13*2^23: 24 prime factors, a(20)=169869312=3^4*2^21: 25 prime factors, a(21)=654311424=13*3*2^24: 26 prime factors. a(19)-1, a(20)-1 and a(21)-1 are primes.
%o A066617 (PARI) {A066617(a, b) = local(p, c, d); forprime(p=a,b,d=bigomega(p+1); if(d>c,c=d; print1(p+1,",")))} A066617(3,10^7)
%Y A066617 Cf. Mersenne Primes + 1: A072868(n)=A000668(n)+1.
%K A066617 nonn
%O A066617 1,1
%A A066617 _G. L. Honaker, Jr._, Jan 13 2002
%E A066617 More terms from _Jason Earls_, Jan 15 2002
%E A066617 More terms from _Hugo Pfoertner_, Sep 10 2004
%E A066617 a(24)-a(27) from _Donovan Johnson_, Dec 08 2009