OFFSET
1,3
COMMENTS
Locally disjoint means no branch of any vertex overlaps a different (unequal) branch of the same vertex.
EXAMPLE
The a(1) = 1 through a(5) = 13 trees:
o (o) (oo) (ooo) (oooo)
((o)) ((o)o) ((o)oo)
((oo)) ((oo)o)
(o(o)) ((ooo))
(((o))) (o(o)o)
(o(oo))
(oo(o))
(((o))o)
(((o)o))
(((oo)))
((o(o)))
(o((o)))
((((o))))
MATHEMATICA
aot[n_]:=If[n==1, {{}}, Join @@ Table[Tuples[aot/@c], {c, Join@@Permutations/@IntegerPartitions[n-1]}]];
Table[Length[Select[aot[n], FreeQ[#, {___, {___, x_, ___}, ___, {___, x_, ___}, ___}]&]], {n, 10}]
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Nov 19 2022
STATUS
approved