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 A188698 #21 Sep 08 2022 08:45:56 %S A188698 1,2,690,33190,57106,77140,135606,258990,303430,331140,337536,359230, %T A188698 375646,455526,458326,493396,548226,550540,585106,602056,659250, %U A188698 680830,742306,800406,827680,870240,918340,925390,968320,1203100,1273890,1455526,1497576,1605016 %N A188698 Numbers k such that 1+k, 1+k^2, 1+k^4 and 1+k^16 are all prime. %C A188698 Subsequence of A070325, which itself is a subsequence of A070689, which itself is a subsequence of A006093. %e A188698 a(3) = 690 = A070689(32) = A070325(11) = A006093(125). %o A188698 (Magma) [n: n in [0..7000000]| IsPrime(1+n) and IsPrime(1+n^2) and IsPrime(1+n^4) and IsPrime(1+n^16)]; // _Vincenzo Librandi_, Apr 11 2011 %K A188698 nonn %O A188698 1,2 %A A188698 _Zak Seidov_, Apr 09 2011 %E A188698 a(1) = 1 prepended by _Vincenzo Librandi_, Apr 11 2011