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A298535 Number of unlabeled rooted trees with n vertices such that every branch of the root has a different number of leaves. 4
1, 1, 1, 2, 5, 13, 32, 80, 200, 511, 1323, 3471, 9183, 24491, 65715, 177363, 481135, 1311340 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..18.

MATHEMATICA

rut[n_]:=rut[n]=If[n===1, {{}}, Join@@Function[c, Union[Sort/@Tuples[rut/@c]]]/@IntegerPartitions[n-1]];

Table[Length[Select[rut[n], UnsameQ@@(Count[#, {}, {0, Infinity}]&/@#)&]], {n, 15}]

CROSSREFS

Cf. A000081, A003238, A004111, A032305, A289079, A290689, A291443, A297791, A298422, A298533, A298536.

Sequence in context: A199812 A255170 A255630 * A110320 A219230 A108890

Adjacent sequences:  A298532 A298533 A298534 * A298536 A298537 A298538

KEYWORD

nonn,more

AUTHOR

Gus Wiseman, Jan 20 2018

STATUS

approved

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Last modified February 23 15:43 EST 2018. Contains 299581 sequences. (Running on oeis4.)