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 A109348 #11 Feb 16 2025 08:32:58 %S A109348 4,5,79,29,4141,37,205339,1241,127639,341,494287399,2041,24221854021, %T A109348 82573,3628081,2885681,58157596211761,109117,2849723505777919,4871281, %U A109348 8607961321,197750389,6842186811484434379,5576881,80962848274370701 %N A109348 Zsigmondy numbers for a = 7, b = 3: Zs(n, 7, 3) is the greatest divisor of 7^n - 3^n that is relatively prime to 7^m - 3^m for all positive integers m < n. %H A109348 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ZsigmondyTheorem.html">Zsigmondy's Theorem</a> %Y A109348 Cf. A064078-A064083, A109325, A109347, A109349. %K A109348 nonn %O A109348 1,1 %A A109348 _Jonathan Vos Post_, Aug 21 2005 %E A109348 Edited, corrected and extended by _Ray Chandler_, Aug 26 2005 %E A109348 Definition corrected by _Jerry Metzger_, Nov 04 2009