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 A168078 #7 Jul 22 2025 07:29:53 %S A168078 1,4,12,32,144,176,1728,4320,27936 %N A168078 Number of matrices with elements 1..n in which every pair of adjacent elements are relatively prime. %C A168078 For prime p, a(p) = 2*A076220(p) %H A168078 Lior Manor, <a href="/A168078/a168078.gif">Illustration of initial terms</a> %Y A168078 Cf. A000005, A076220 %K A168078 more,nonn %O A168078 1,2 %A A168078 _Lior Manor_, Nov 18 2009