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A331684 Number of locally disjoint enriched identity p-trees of weight n. 5

%I #6 Feb 01 2020 07:09:30

%S 1,1,2,3,6,14,30,68,157,379,901,2229,5488,13846,34801,89368,228186,

%T 592943,1533511,4026833

%N Number of locally disjoint enriched identity p-trees of weight n.

%C A locally disjoint enriched identity p-tree of weight n is either the number n itself or a finite sequence of distinct non-overlapping locally disjoint enriched identity p-trees whose weights are weakly decreasing and sum to n.

%e The a(1) = 1 through a(6) = 14 enriched p-trees:

%e 1 2 3 4 5 6

%e (21) (31) (32) (42)

%e ((21)1) (41) (51)

%e ((21)2) (321)

%e ((31)1) ((21)3)

%e (((21)1)1) ((31)2)

%e ((32)1)

%e (3(21))

%e ((41)1)

%e ((21)21)

%e (((21)1)2)

%e (((21)2)1)

%e (((31)1)1)

%e ((((21)1)1)1)

%t disjointQ[u_]:=Apply[And,Outer[#1==#2||Intersection[#1,#2]=={}&,u,u,1],{0,1}];

%t ldeip[n_]:=Prepend[Select[Join@@Table[Tuples[ldeip/@p],{p,Rest[IntegerPartitions[n]]}],UnsameQ@@#&&disjointQ[DeleteCases[#,_Integer]]&],n];

%t Table[Length[ldeip[n]],{n,12}]

%Y The orderless version is A316694.

%Y The non-identity version is A331687.

%Y Identity trees are A004111.

%Y P-trees are A196545.

%Y Enriched p-trees are A289501.

%Y Locally disjoint identity trees are A316471.

%Y Enriched identity p-trees are A331875, with locally disjoint case A331687.

%Y Cf. A000669, A005804, A141268, A300660, A316696, A316697, A331678, A331679, A331680, A331683, A331686, A331783, A331874.

%K nonn,more

%O 1,3

%A _Gus Wiseman_, Jan 31 2020

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Last modified April 17 23:23 EDT 2024. Contains 371767 sequences. (Running on oeis4.)