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 A234939 #21 Feb 02 2025 10:13:42 %S A234939 1,2,8,38,200,1124,6608,40142,249992,1587548,10241264,66926204, %T A234939 442120016,2947660616,19808372384,134030802782,912385334792, %U A234939 6244056445868,42935538999728,296493196682036,2055313327353200,14297177397185912,99769106353379168,698228176760193068 %N A234939 Coefficients of Hilbert series for suboperad of bicolored noncrossing configurations generated by a triangle with colored base and at least one more colored edge and a triangle with one colored non-base edge. %H A234939 Frédéric Chapoton and Samuele Giraudo, <a href="https://arxiv.org/abs/1310.4521">Enveloping operads and bicoloured noncrossing configurations</a>, arXiv preprint arXiv:1310.4521 [math.CO], 2013-2014. %F A234939 a(n) = 2 * A007564(n-1) for n > 1 [from Chapoton & Giraudo, Proposition 3.8]. - _Andrey Zabolotskiy_, Feb 01 2025 %Y A234939 Cf. A234938, A052701, A007863, A006013, A006318, A007564. %K A234939 nonn %O A234939 1,2 %A A234939 _N. J. A. Sloane_, Jan 04 2014 %E A234939 Terms a(9) onwards added and name clarified by _Andrey Zabolotskiy_, Feb 02 2025