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 A043027 #9 Aug 22 2021 14:54:51 %S A043027 7,63,455,463,471,479,487,495,503,511,3591,3663,3735,3807,3879,3951, %T A043027 4023,4095,28679,28743,28807,28871,28935,28999,29063,29127,29199, %U A043027 29263,29327,29391,29455,29519,29583,29647,29719,29783 %N A043027 Base-8 palindromes that start with 7. %Y A043027 Cf. A007094. %K A043027 nonn,base %O A043027 1,1 %A A043027 _Clark Kimberling_