A324843 Number of unlabeled rooted trees with n nodes where the branches of any branch of any terminal subtree form a submultiset of the branches of the same subtree.
1, 1, 1, 2, 2, 4, 4, 8, 9, 15, 17, 31, 35, 57, 70, 111, 136, 213, 265, 405, 517, 763, 987, 1458, 1893, 2736, 3611, 5161, 6836, 9702
Offset: 1
Examples
The a(1) = 1 through a(8) = 8 rooted trees: o (o) (oo) (ooo) (oooo) (ooooo) (oooooo) (ooooooo) (o(o)) (oo(o)) (oo(oo)) (ooo(oo)) (ooo(ooo)) (ooo(o)) (oooo(o)) (oooo(oo)) (o(o)(o)) (oo(o)(o)) (ooooo(o)) (oo(o)(oo)) (ooo(o)(o)) (o(o)(o)(o)) (o(o)(o(o)))
Crossrefs
Programs
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Mathematica
submultQ[cap_,fat_]:=And@@Function[i,Count[fat,i]>=Count[cap,i]]/@Union[List@@cap]; rallt[n_]:=Select[Union[Sort/@Join@@(Tuples[rallt/@#]&/@IntegerPartitions[n-1])],And@@Table[submultQ[b,#],{b,#}]&]; Table[Length[rallt[n]],{n,10}]
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