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A038084 Number of n-node rooted identity trees of height at most 5. 5
1, 1, 1, 2, 3, 6, 11, 19, 31, 52, 85, 140, 228, 370, 594, 954, 1519, 2412, 3814, 6006, 9419, 14726, 22938, 35612, 55125, 85065, 130900, 200875, 307446, 469342, 714784, 1085956, 1646160, 2489838, 3757929, 5660110, 8508224, 12764585, 19114360, 28570525, 42629077 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

A finite sequence with A038093(5) = 3211265 terms.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1000

N. J. A. Sloane, Transforms

Index entries for sequences related to rooted trees

FORMULA

Take Weigh transform of A038083 and shift right.

MAPLE

weigh:= proc(p) proc(n) `if`(n<0, 1, coeff(mul((1+x^k)^p(k), k=1..n), x, n)) end end: wsh:= p-> n-> weigh(p)(n-1): a:= (wsh@@2)(n-> `if`(n>0 and n<12, [1$3, 2$5, 1$3][n], 0)): seq(a(n), n=1..50); # Alois P. Heinz, Sep 10 2008

MATHEMATICA

Nest[CoefficientList[Series[Product[(1+x^i)^#[[i]], {i, 1, Length[#]}], {x, 0, 40}], x]&, {1}, 5] (* Geoffrey Critzer, Aug 01 2013 *)

CROSSREFS

Cf. A038081-A038093.

Sequence in context: A288583 A090036 A024971 * A018169 A238644 A191629

Adjacent sequences:  A038081 A038082 A038083 * A038085 A038086 A038087

KEYWORD

nonn,fini

AUTHOR

Christian G. Bower, Jan 04 1999

STATUS

approved

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Last modified November 21 01:33 EST 2019. Contains 329349 sequences. (Running on oeis4.)