A316501
Number of unlabeled rooted trees with n nodes in which the branches of any node with more than one distinct branch have empty intersection.
Original entry on oeis.org
1, 1, 2, 4, 9, 19, 45, 103, 250, 611, 1528, 3853, 9875, 25481, 66382, 174085, 459541, 1219462
Offset: 1
The a(6) = 19 rooted trees:
(((((o)))))
((((oo))))
(((o(o))))
(((ooo)))
((o((o))))
((o(oo)))
(((o)(o)))
((oo(o)))
((oooo))
(o(((o))))
(o((oo)))
(o(o(o)))
(o(ooo))
((o)((o)))
(oo((o)))
(oo(oo))
(o(o)(o))
(ooo(o))
(ooooo)
-
strut[n_]:=strut[n]=If[n===1,{{}},Select[Join@@Function[c,Union[Sort/@Tuples[strut/@c]]]/@IntegerPartitions[n-1],Or[Length[Union[#]]==1,Intersection@@#=={}]&]];
Table[Length[strut[n]],{n,15}]
A317785
Number of locally connected rooted trees with n nodes.
Original entry on oeis.org
1, 1, 1, 1, 2, 2, 4, 4, 7, 8, 12, 14, 21, 24, 34, 42, 55, 67, 91, 109, 144, 177, 228, 281, 366, 448, 579, 720, 916, 1142
Offset: 1
The a(11) = 12 locally connected rooted trees:
((((((((((o))))))))))
((((((((o)(o))))))))
(((((((o))((o)))))))
((((((o)))(((o))))))
(((((o))))((((o)))))
((((((o)(o)(o))))))
(((((o))((o)(o)))))
((((o))((o))((o))))
((((o)(o)(o)(o))))
(((o))((o)(o)(o)))
(((o)(o))((o)(o)))
((o)(o)(o)(o)(o))
Cf.
A000081,
A276625,
A286518,
A286520,
A301700,
A304714,
A316473,
A316475,
A317077,
A317078,
A317708,
A317787.
-
multijoin[mss__]:=Join@@Table[Table[x, {Max[Count[#, x]&/@{mss}]}], {x, Union[mss]}];
csm[s_]:=With[{c=Select[Tuples[Range[Length[s]],2],And[OrderedQ[#],UnsameQ@@#,Length[Intersection@@s[[#]]]>0]&]},If[c=={},s,csm[Union[Append[Delete[s,List/@c[[1]]],multijoin@@s[[c[[1]]]]]]]]];
rurt[n_]:=If[n==1,{{}},Join@@Table[Select[Union[Sort/@Tuples[rurt/@ptn]],Or[Length[#]==1,Length[csm[#]]==1]&],{ptn,IntegerPartitions[n-1]}]];
Table[Length[rurt[n]],{n,10}]
A319271
Number of series-reduced locally non-intersecting aperiodic rooted trees with n nodes.
Original entry on oeis.org
1, 1, 0, 1, 1, 3, 3, 9, 12, 27, 42, 91, 151, 312, 550, 1099, 2026, 3999, 7527, 14804, 28336, 55641, 107737, 211851, 413508, 814971, 1600512, 3162761, 6241234
Offset: 1
The a(8) = 9 rooted trees:
(o(o(o(o))))
(o(o(o)(o)))
(o(ooo(o)))
(oo(oo(o)))
(o(o)(o(o)))
(ooo(o(o)))
(o(o)(o)(o))
(ooo(o)(o))
(ooooo(o))
Cf.
A000081,
A000837,
A007562,
A289509,
A301700,
A303431,
A316470,
A316473,
A316475,
A316495,
A319270.
-
btrut[n_]:=btrut[n]=If[n===1,{{}},Select[Join@@Function[c,Union[Sort/@Tuples[btrut/@c]]]/@IntegerPartitions[n-1],And[Intersection@@#=={},GCD@@Length/@Split[#]==1]&]];
Table[Length[btrut[n]],{n,30}]
A358460
Number of locally disjoint ordered rooted trees with n nodes.
Original entry on oeis.org
1, 1, 2, 5, 13, 36, 103, 301, 902, 2767, 8637, 27324, 87409, 282319, 919352
Offset: 1
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))))
-
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}]
A319286
Number of series-reduced locally disjoint rooted trees whose leaves span an initial interval of positive integers with multiplicities an integer partition of n.
Original entry on oeis.org
1, 2, 9, 67, 573, 6933, 97147, 1666999
Offset: 1
The a(3) = 9 trees:
(1(11))
(111)
(1(12))
(2(11))
(112)
(1(23))
(2(13))
(3(12))
(123)
Examples of rooted trees that are not locally disjoint are ((11)(12)) and ((12)(13)).
-
disjointQ[u_]:=Apply[And,Outer[#1==#2||Intersection[#1,#2]=={}&,u,u,1],{0,1}];
sps[{}]:={{}};sps[set:{i_,_}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,_}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
gro[m_]:=gro[m]=If[Length[m]==1,{m},Select[Union[Sort/@Join@@(Tuples[gro/@#]&/@Select[mps[m],Length[#]>1&])],disjointQ]];
Table[Sum[Length[gro[m]],{m,Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n]}],{n,5}]
A319285
Number of series-reduced locally stable rooted trees whose leaves span an initial interval of positive integers with multiplicities an integer partition of n.
Original entry on oeis.org
1, 2, 9, 69, 619, 7739, 109855, 1898230
Offset: 1
The a(3) = 9 trees:
(1(11))
(111)
(1(12))
(2(11))
(112)
(1(23))
(2(13))
(3(12))
(123)
Examples of rooted trees that are not locally stable are ((11)(111)), ((11)(112)), ((12)(112)), ((12)(123)).
-
submultisetQ[M_,N_]:=Or[Length[M]==0,MatchQ[{Sort[List@@M],Sort[List@@N]},{{x_,Z___},{_,x_,W___}}/;submultisetQ[{Z},{W}]]];
stableQ[u_]:=Apply[And,Outer[#1==#2||!submultisetQ[#1,#2]&&!submultisetQ[#2,#1]&,u,u,1],{0,1}];
sps[{}]:={{}};sps[set:{i_,_}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,_}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
gro[m_]:=gro[m]=If[Length[m]==1,{m},Select[Union[Sort/@Join@@(Tuples[gro/@#]&/@Select[mps[m],Length[#]>1&])],stableQ]];
Table[Sum[Length[gro[m]],{m,Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n]}],{n,5}]
A319291
Number of series-reduced locally disjoint rooted trees with n leaves spanning an initial interval of positive integers.
Original entry on oeis.org
1, 2, 12, 107, 1299, 20764, 412957, 9817743
Offset: 1
The a(3) = 12 series-reduced locally disjoint rooted trees:
(1(11))
(111)
(1(22))
(2(12))
(122)
(1(12))
(2(11))
(112)
(1(23))
(2(13))
(3(12))
(123)
The trees counted by A316651(4) but not by a(4):
((11)(12))
((12)(13))
((12)(22))
((12)(23))
((13)(23))
Cf.
A000081,
A007562,
A301700,
A316473,
A316475,
A316495,
A316651,
A316694,
A316695,
A316696,
A316697,
A319286.
-
disjointQ[u_]:=Apply[And,Outer[#1==#2||Intersection[#1,#2]=={}&,u,u,1],{0,1}];
sps[{}]:={{}};sps[set:{i_,_}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,_}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
gro[m_]:=gro[m]=If[Length[m]==1,{m},Select[Union[Sort/@Join@@(Tuples[gro/@#]&/@Select[mps[m],Length[#]>1&])],disjointQ]];
allnorm[n_Integer]:=Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1];
Table[Sum[Length[gro[m]],{m,allnorm[n]}],{n,5}]
A319292
Number of series-reduced locally nonintersecting rooted trees whose leaves span an initial interval of positive integers with multiplicities an integer partition of n.
Original entry on oeis.org
1, 1, 6, 48, 455, 5700, 83138, 1454870
Offset: 1
The a(3) = 6 trees are: (1(12)), (112), (1(23)), (2(13)), (3(12)), (123). Missing from this list but counted by A316651 are: (1(11)), (2(11)), (111).
-
nonintQ[u_]:=Intersection@@u=={};
sps[{}]:={{}};sps[set:{i_,_}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,_}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
gro[m_]:=gro[m]=If[Length[m]==1,{m},Select[Union[Sort/@Join@@(Tuples[gro/@#]&/@Select[mps[m],Length[#]>1&])],nonintQ]];
Table[Sum[Length[gro[m]],{m,Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n]}],{n,5}]
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