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A245750 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 5. 2
1, 7, 26, 91, 291, 885, 2588, 7373, 20555, 56413, 152812, 409696, 1089029, 2874506, 7542257, 19690939, 51188137, 132579401, 342294012, 881292334, 2263535926, 5801350565, 14840644204, 37901021924, 96650247055, 246137463494, 626087267035, 1590840361215 (list; graph; refs; listen; history; text; internal format)
OFFSET

15,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 15..1000

MAPLE

b:= proc(n, i, t, k) option remember; `if`(n=0, 1,

      `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*

       b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))

    end:

a:= n-> b(n-1$2, 5$2) -b(n-1$2, 4$2):

seq(a(n), n=15..60);

CROSSREFS

Column k=5 of A244523.

Sequence in context: A282703 A240256 A279761 * A268776 A050476 A026617

Adjacent sequences:  A245747 A245748 A245749 * A245751 A245752 A245753

KEYWORD

nonn

AUTHOR

Joerg Arndt and Alois P. Heinz, Jul 31 2014

STATUS

approved

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Last modified July 7 14:34 EDT 2020. Contains 335495 sequences. (Running on oeis4.)