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 A361240 #8 Mar 11 2023 00:13:41 %S A361240 1,1,1,4,19,124,931,7801,68685,630850,5966610,57808920,571178751, %T A361240 5737672339,58455577800,602859484608,6283968796705,66119472527814, %U A361240 701526880303315,7498841163925819,80696081185766970,873654670250482120,9510760874015305314,104056578392127906720 %N A361240 Number of nonequivalent noncrossing triangular cacti with n triangles up to rotation and reflection. %H A361240 Andrew Howroyd, <a href="/A361240/b361240.txt">Table of n, a(n) for n = 0..500</a> %F A361240 a(2*n) = (A361237(2*n) + A002294(n))/2; a(2*n+1) = (A361237(2*n+1) + A118970(n))/2. %Y A361240 Column 3 of A361239. %Y A361240 Cf. A002294, A118970, A361237. %K A361240 nonn %O A361240 0,4 %A A361240 _Andrew Howroyd_, Mar 06 2023