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 A047761 #15 Mar 07 2020 01:21:50 %S A047761 0,1,1,3,5,12,23,55,114,273,588,1428,3156,7752,17427,43263,98516, %T A047761 246675,567281,1430715,3316521,8414640,19633796,50067108,117464424, %U A047761 300830572,709098696,1822766520,4313876888,11124755664,26421284043 %N A047761 a(n) = A047760(2n+1). %H A047761 L. W. Beineke and R. E. Pippert, <a href="http://dx.doi.org/10.4153/CJM-1974-006-x">Enumerating dissectable polyhedra by their automorphism groups</a>, Canad. J. Math., 26 (1974), 50-67. %H A047761 S. J. Cyvin, Jianji Wang, J. Brunvoll, Shiming Cao, Ying Li, B. N. Cyvin, and Yugang Wang, <a href="https://doi.org/10.1016/S0022-2860(97)00025-2">Staggered conformers of alkanes: complete solution of the enumeration problem</a>, J. Molec. Struct. 413-414 (1997), 227-239. %F A047761 a(2n-1) = binomial(3n, n)/(2n+1) = A001764(n). %K A047761 nonn %O A047761 0,4 %A A047761 _N. J. A. Sloane_