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 A081156 #10 Jan 11 2024 09:03:38 %S A081156 1,1,2,3,6,12,20,59,120 %N A081156 Number of odd cycles in range [A014137(2n)..A014138(2n)] of permutation A057505/A057506, with fixed-points of both A057163 and A057164. %C A081156 See comment at A080973. %F A081156 a(n) = A081155(2n+1) = A000108(n) - 2*A081163(n). %Y A081156 Cf. A080973. %Y A081156 Cf. A081155, A000108, A081163. %Y A081156 Cf. A014137, A014138, A057505, A057506, A057163, A057164. %K A081156 nonn,more %O A081156 0,3 %A A081156 _Wouter Meeussen_ & _Antti Karttunen_ Mar 10 2003