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A038092
Number of n-node rooted identity trees of height 8.
3
1, 7, 27, 82, 221, 553, 1323, 3078, 7019, 15765, 34992, 76922, 167697, 363020, 780937, 1670786, 3557060, 7539856, 15918972, 33490067, 70226358, 146822144, 306121101, 636648253, 1320964417, 2734901341, 5650875038, 11653922283, 23991828701, 49310264440
OFFSET
9,2
COMMENTS
The number of terms with a(n)>0 is A038093(8) - 8. - Alois P. Heinz, Sep 22 2013
FORMULA
MATHEMATICA
f[n_]:=Nest[CoefficientList[Series[Product[(1+x^i)^#[[i]], {i, 1, Length[#]}], {x, 0, 50}], x]&, {1}, n]; Drop[f[8]-PadRight[f[7], Length[f[8]]], 8] (* Geoffrey Critzer, Aug 01 2013 *)
CROSSREFS
Column k=8 of A227819.
Sequence in context: A027180 A036597 A338230 * A059823 A339771 A059769
KEYWORD
nonn,fini
AUTHOR
Christian G. Bower, Jan 04 1999
STATUS
approved