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 A081161 #7 Jan 11 2024 09:09:10 %S A081161 0,1,4,16,60,225,848,3188,12095 %N A081161 Number of even cycles in range [A014137(2n)..A014138(2n)] of permutation A057505/A057506, with two fixed-points of A057164. %F A081161 a(n) = A081160(2n+1). %Y A081161 Cf. A081160, A014137, A014138, A057505, A057506, A057164. %K A081161 nonn,more %O A081161 0,3 %A A081161 _Wouter Meeussen_ and _Antti Karttunen_, Mar 10 2003