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 A268660 #19 Apr 03 2023 10:36:13 %S A268660 2,5,8,41,209,353,2816,20909,42665,157169,213321,303093,362765,382449, %T A268660 2145353,2478785 %N A268660 Numbers n such that 3*2^n + 1 is a prime factor of a generalized Fermat number 12^(2^m) + 1 for some m. %D A268660 Wilfrid Keller, private communication, 2008. %H A268660 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-98-00891-6">Factors of generalized Fermat numbers</a>, Math. Comp. 67 (1998), no. 221, pp. 441-446. %H A268660 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-05-01816-8">Table errata to “Factors of generalized Fermat numbers”</a>, Math. Comp. 74 (2005), no. 252, p. 2099. %H A268660 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-10-02371-9">Table errata 2 to "Factors of generalized Fermat numbers"</a>, Math. Comp. 80 (2011), pp. 1865-1866. %H A268660 C. K. Caldwell, Top Twenty page, <a href="https://t5k.org/top20/page.php?id=11">Generalized Fermat Divisors (base=12)</a> %H A268660 OEIS Wiki, <a href="/wiki/Generalized_Fermat_numbers">Generalized Fermat numbers</a> %Y A268660 Cf. A152585, A268657, A268658, A204620, A268659, A268661, A268662, A268663, A226366, A268664. Subsequence of A002253. %K A268660 nonn,hard,more %O A268660 1,1 %A A268660 _Arkadiusz Wesolowski_, Feb 10 2016