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 A113017 #11 Feb 16 2025 08:32:59 %S A113017 13,19,23,29,41,43,47,53,59,71,73,79,83,89,97,101,103,109,113,127,137, %T A113017 139,149,151,163,173,179,191,193,197,199,211,223,227,229,233,239,257, %U A113017 263,269,281,283,293,311,313,317,331,337,349,353,359,367,373,379,383 %N A113017 Primes that become composites when their decimal representation is interpreted duodecimally. %H A113017 Robert Price, <a href="/A113017/b113017.txt">Table of n, a(n) for n = 1..26358</a> %H A113017 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Duodecimal.html">Duodecimal</a> %e A113017 A000040(25)=97 -> 9*12^1+7*12^0=108+7=115=5*23. %Y A113017 Cf. A000040, A002808, A113016, A102487. %K A113017 nonn,base %O A113017 1,1 %A A113017 _Reinhard Zumkeller_, Oct 11 2005