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 A174083 #18 May 18 2025 17:54:36 %S A174083 4,0,40,168,1652,9408,117896,1019260,12737856,140794368,2072921376, %T A174083 25990014896,439692361160 %N A174083 Number of circular permutations of length n with no consecutive triples (i, i+d, i+2d) (mod n) for all d. %C A174083 Circular permutations are permutations whose indices are from the ring of integers modulo n. %e A174083 For n=5 since a(5)=0 all (5-1)! = 24 circular permutations of length 5 have some consecutive triple (i, i+d, i+2d) (mod 5). For example, the permutation (0,4,2,1,3) has a triple (1,3,0) with d=2. This is clearly a special case. %Y A174083 Cf. A165962, A174075, A174080, A174081, A174082. %K A174083 nonn,more %O A174083 4,1 %A A174083 _Isaac Lambert_, Mar 15 2010 %E A174083 a(10)-a(13) from _Andrey Goder_, Jul 03 2022 %E A174083 a(14)-a(16) from _Bert Dobbelaere_, May 18 2025