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 A072288 #36 Feb 21 2025 08:22:48 %S A072288 316912650057057350374175801344000001 %N A072288 Smallest prime factor of googolplex + n that exceeds 13, or 1 if googolplex + n is 13-smooth. %C A072288 a(2) is not known. After a(1) the sequence continues ?, 1429, 1129, 29, ?, 53, 427169, 5501, 19, 59, 1327, 1645318771, 61, 211, 17, 1831, ?, 43, 389, 173, 233886337, 139, 1451, 18797, 31, 37, 8297, 19, 13879, ?, 9241, 17, 29, ... %C A072288 The question marks indicate terms > 10^14. - _Dario Alpern_, May 17 2003 %H A072288 Tanya Khovanova, <a href="https://www.tanyakhovanova.com/RecursiveSequences/NonRecursions.html">Non Recursions</a> %H A072288 Dario Alejandro Alpern, <a href="https://www.alpertron.com.ar/GOOGOL.HTM">Factors of 1000 numbers starting from googolplex</a> %H A072288 Robert Harley, <a href="https://pauillac.inria.fr/~harley/bits.html">Factors of Googolplex+1</a> (Found some terms) %H A072288 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Googolplex.html">Googolplex</a> %H A072288 <a href="/index/O#oneterm">Index entries for one-term sequences</a> %t A072288 (* For any individual n *) k = 17; While[ !PrimeQ[k] || PowerMod[10, 10^100, k] + n != k, k += 2]; k %Y A072288 Cf. A067007, A078814, A341116. %K A072288 hard,nonn,bref,more,less %O A072288 1,1 %A A072288 _Ed Pegg Jr_ and _Robert G. Wilson v_, Nov 21 2002 %E A072288 Name edited by _Peter Munn_, Feb 20 2025