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 A115901 #5 Jul 15 2021 21:24:14 %S A115901 1,2,3,4,71,116,7271,43585895 %N A115901 Numbers k such that prime(k) - k and prime(k) + k are palindromes. %C A115901 Intersection of A115884 and A115885. %e A115901 prime(43585895) - 43585895 = 806494608 and %e A115901 prime(43585895) + 43585895 = 893666398. %Y A115901 Cf. A115884, A115885. %K A115901 nonn,base %O A115901 1,2 %A A115901 _Giovanni Resta_, Feb 06 2006