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 A322752 #17 Feb 06 2025 21:31:04
%S A322752 0,2,3,9,30,110,423,1706,7085,30186,131071,578194,2583377,11667874,
%T A322752 53180604,244301512,1129947243,5257592237,24592945975,115578827200,
%U A322752 545478791124,2584216074295,12285025045259,58584860422121,280181867792399,1343499543045511,6457845289959966
%N A322752 Number of "funny trees" on n nodes.
%C A322752 For precise definition see Example 15.3.7 of Bona (2015).
%C A322752 The trees considered here have nodes of two types: black and white. The child nodes of black nodes are unordered and can be either black or white. The child nodes of white nodes are linearly ordered and must be black. - _Andrew Howroyd_, Feb 06 2025
%D A322752 Miklos Bona, editor, Handbook of Enumerative Combinatorics, CRC Press, 2015, page 1002.
%H A322752 Andrew Howroyd, <a href="/A322752/b322752.txt">Table of n, a(n) for n = 0..500</a>
%H A322752 N. J. A. Sloane, <a href="/A322059/a322059.jpg">Annotated scan of page 1001 of Bona (2015).</a>
%H A322752 N. J. A. Sloane, <a href="/A322059/a322059_1.jpg">Annotated scan of page 1002 of Bona (2015).</a>
%o A322752 (PARI) EulerT(v)={Vec(exp(x*Ser(dirmul(v,vector(#v,n,1/n))))-1, -#v)}
%o A322752 seq(n)={my(w=O(x),b=O(x)); for(n=1, n, w=x/(1-b); b=x*(1 + x*Ser(EulerT(Vec(b+w))))); Vec(b+w, -n-1)} \\ _Andrew Howroyd_, Feb 06 2025
%Y A322752 Cf. A277996.
%K A322752 nonn
%O A322752 0,2
%A A322752 _N. J. A. Sloane_, Dec 25 2018
%E A322752 Offset corrected and a(7) onwards from _Andrew Howroyd_, Feb 06 2025