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 A300797 #11 Aug 26 2018 02:34:29
%S A300797 1,1,1,1,2,2,4,6,11,17,34,59,118,213,424,799,1606,3072,6216,12172,
%T A300797 24650,48710,99333,198237,405526,815267,1673127,3387165,6974702,
%U A300797 14179418,29285048,59841630,123848399,253927322,526936694,1084022437,2253778793,4649778115
%N A300797 Number of strict trees of weight 2n + 1 in which all outdegrees and all leaves are odd.
%C A300797 A strict tree of weight n > 0 is either a single node of weight n, or a sequence of two or more strict trees with strictly decreasing weights summing to n.
%H A300797 Andrew Howroyd, <a href="/A300797/b300797.txt">Table of n, a(n) for n = 0..500</a>
%e A300797 The a(7) = 6 strict trees: 15, (11 3 1), (9 5 1), (7 5 3), ((7 3 1) 3 1), ((5 3 1) 5 1).
%t A300797 a[n_]:=a[n]=If[OddQ[n],1,0]+Sum[Times@@a/@ptn,{ptn,Select[IntegerPartitions[n],Length[#]>1&&OddQ[Length[#]]&&UnsameQ@@#&]}];
%t A300797 Table[a[n],{n,1,60,2}]
%o A300797 (PARI) seq(n)={my(v=vector(n)); for(n=1, n, v[n] = 1 + polcoef(prod(k=1, n-1, 1 + v[k]*x^(2*k-1) + O(x^(2*n))) - prod(k=1, n-1, 1 - v[k]*x^(2*k-1) + O(x^(2*n))), 2*n-1)/2); v} \\ _Andrew Howroyd_, Aug 26 2018
%Y A300797 Cf. A000009, A000992, A032305, A063834, A078408, A089259, A196545, A273873, A279785, A289501, A298118, A300301, A300352, A300353, A300436, A300439, A300440, A300652.
%K A300797 nonn
%O A300797 0,5
%A A300797 _Gus Wiseman_, Mar 13 2018
%E A300797 a(30)-a(37) from _Alois P. Heinz_, Mar 13 2018