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 A302916 #5 Apr 16 2018 18:56:38
%S A302916 1,1,2,4,11,22,74,174,530,1302,4713,10639,40877,101795,325609,925733,
%T A302916 3432819,8078511,32542036,82226383,279096823,795532677,3066505569,
%U A302916 7374764180,28946183035,79313174765,275507514909,772692247626,3049937788372,7071057261148
%N A302916 Number of relatively prime p-trees of weight n.
%C A302916 A relatively prime p-tree of weight n is either a single node, or a finite sequence of two or more relatively prime p-trees whose weights are weakly decreasing, relatively prime, and sum to n.
%e A302916 The a(4) = 4 relatively prime p-trees are (((oo)o)o), ((ooo)o), ((oo)oo), (oooo). Missing from this list is the p-tree ((oo)(oo)).
%t A302916 a[n_]:=a[n]=If[n===1,1,Sum[Times@@a/@y,{y,Rest[Select[IntegerPartitions[n],Or[Length[#]===1,GCD@@#===1]&]]}]];
%t A302916 Array[a,20]
%Y A302916 Cf. A000081, A000837, A003238, A004111, A055277, A093637, A196545, A289501, A290689, A300486, A301462, A301467, A302094, A302915, A302917.
%K A302916 nonn
%O A302916 1,3
%A A302916 _Gus Wiseman_, Apr 15 2018