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 A177134 #14 Mar 16 2025 23:59:06 %S A177134 5,23,2003,200003,2000003,20000003,2000000000003,20000000000000003, %T A177134 200000000000000003,20000000000000000000003,2000000000000000000000003, %U A177134 200000000000000000000000000000000003 %N A177134 Primes of the form 2*10^k + 3. %H A177134 Makoto Kamada, <a href="https://stdkmd.net/nrr/2/20003.htm#prime">Prime numbers of the form 200...003</a>. %F A177134 a(n) = A173041(A081677(n)). %o A177134 (Magma) [ a: n in [0..250] | IsPrime(a) where a is 2*10^n + 3 ]; %Y A177134 Cf. A081677, A101951, A173041. %K A177134 nonn %O A177134 1,1 %A A177134 _Vincenzo Librandi_, Dec 10 2010