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 A316475 Number of locally stable rooted trees with n nodes, meaning no branch is a submultiset of any other (unequal) branch of the same root. 24
 1, 1, 2, 3, 5, 7, 14, 25, 50, 101, 207, 426, 902, 1917, 4108, 8887, 19335, 42330, 93130, 205894, 456960, 1018098, 2275613, 5102248, 11471107, 25856413 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE The a(6) = 7 locally stable rooted trees: (((((o))))) ((((oo)))) (((ooo))) (((o)(o))) ((oooo)) ((o)((o))) (ooooo) MATHEMATICA submultisetQ[M_, N_]:=Or[Length[M]==0, MatchQ[{Sort[List@@M], Sort[List@@N]}, {{x_, Z___}, {___, x_, W___}}/; submultisetQ[{Z}, {W}]]] strut[n_]:=strut[n]=If[n===1, {{}}, Select[Join@@Function[c, Union[Sort/@Tuples[strut/@c]]]/@IntegerPartitions[n-1], Select[Tuples[#, 2], UnsameQ@@#&&submultisetQ@@#&]=={}&]]; Table[Length[strut[n]], {n, 15}] CROSSREFS Cf. A000081, A285572, A285573, A303362, A304713, A316468, A316470, A316473, A316474. Sequence in context: A005629 A028304 A324840 * A303875 A228652 A157833 Adjacent sequences:  A316472 A316473 A316474 * A316476 A316477 A316478 KEYWORD nonn,more AUTHOR Gus Wiseman, Jul 04 2018 EXTENSIONS a(21)-a(26) from Robert Price, Sep 13 2018 STATUS approved

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Last modified December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)