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 A174081 #6 May 18 2025 18:08:56 %S A174081 16,40,300,1764,17056,118908,1466840,14079340,184672896,2206738248, %T A174081 33901722288,458478528000 %N A174081 Number of permutations of length n with no consecutive triples i,i+d,i+2d (mod n) for all d. %e A174081 For n=4, there are 4!-a(4)=8 permutations with some consecutive triple i,i+d,i+2d (mod 4). Here only d=1 and d=3 works, and the permutations are (0,1,2,3), (1,2,3,0), (2,3,0,1), (3,0,1,2), (0,3,2,1), (3,2,1,0), (2,1,0,3), and (1,0,3,2) %Y A174081 Cf. A095816, A174073, A174080, A174082, A174083. %K A174081 nonn %O A174081 4,1 %A A174081 _Isaac Lambert_, Mar 15 2010 %E A174081 a(10)-a(15) from _Bert Dobbelaere_, May 18 2025