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 A378339 #7 Nov 25 2024 16:29:13 %S A378339 1,2,5,15,46,139,449,1448,4799,15971,54107,184048,633365,2188644, %T A378339 7624153,26659774,93772014,330946542,1173233805,4171572088, %U A378339 14884905583,53249784377,191043396323,686956509123,2476044740337,8942288625630,32360306616473,117309644377341 %N A378339 Number of n-node connected achiral planar maps with an external face in which all internal faces are triangles. %H A378339 Andrew Howroyd, <a href="/A378339/b378339.txt">Table of n, a(n) for n = 3..200</a> %o A378339 (PARI) A378339seq(30) \\ See PARI link in A378340 for program code. %Y A378339 Row sums of A378340. %Y A378339 Cf. A377785 (unsensed), A378335 (sensed), A378341 (by faces), A378342 (by edges). %K A378339 nonn %O A378339 3,2 %A A378339 _Andrew Howroyd_, Nov 24 2024