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 A118328 #19 Feb 16 2025 08:33:01 %S A118328 52,276,25477 %N A118328 Integer lengths of Catalan-primes: numbers n such that the concatenation of the first n decimal digits of Catalan's constant is prime. %H A118328 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CatalansConstantDigits.html">Catalan's Constant Digits</a> %H A118328 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a> %H A118328 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a> %e A118328 C = 0.915965594177..., so a(1) = 52 (the 52-digit number 915965...6721 is the 1st prime in the digit string). %Y A118328 Cf. A006752, A118329. %K A118328 nonn,more,bref,base %O A118328 1,1 %A A118328 _Eric W. Weisstein_, Apr 24 2006 %E A118328 a(3) = 25477 from _Eric W. Weisstein_, May 05 2006 %E A118328 Edited by _Charles R Greathouse IV_, Apr 27 2010