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 A177026 #13 Sep 16 2024 12:00:21 %S A177026 5,449,144114913197948929,5070602400617769700807459995649, %T A177026 11417981541647673977863886842678355104249151489 %N A177026 Primes of the form 4^k*(2^k-1)+1. %C A177026 a(6) has 288 digits. %F A177026 a(n) = 8^A098856(n)-4^A098856(n)+1. %o A177026 (Magma) [a: n in [0..350]|IsPrime(a) where a is 8^n-4^n+1^n]; %Y A177026 Cf. A098856, A155629 %K A177026 nonn,less %O A177026 1,1 %A A177026 _Vincenzo Librandi_, Dec 09 2010