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A000439
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Powers of rooted tree enumerator.
(Formerly M4608 N1965)
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1
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9, 30, 69, 133, 230, 369, 560, 814, 1143, 1560, 2079, 2715, 3484, 4403, 5490, 6764, 8245, 9954, 11913, 14145, 16674, 19525, 22724, 26298, 30275, 34684, 39555, 44919, 50808, 57255, 64294, 71960, 80289, 89318, 99085, 109629, 120990, 133209, 146328, 160390, 175439, 191520, 208679
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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REFERENCES
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J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 150.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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G.f.: (2*x^3 - 9*x^2 + 15*x - 9)/(x - 1)^5. - Jinyuan Wang, Mar 17 2020
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MAPLE
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MATHEMATICA
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Table[(n^4 + 18 n^3 + 83 n^2 + 114 n) / 24, {n, 50}] (* Vincenzo Librandi, Mar 18 2020 *)
LinearRecurrence[{5, -10, 10, -5, 1}, {9, 30, 69, 133, 230}, 50] (* Harvey P. Dale, May 15 2023 *)
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PROG
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(PARI) a(n) = (n^4 + 18*n^3 + 83*n^2 + 114*n)/24; \\ Jinyuan Wang, Mar 17 2020
(Magma) [(n^4 + 18*n^3 + 83*n^2 + 114*n)/24: n in [1..50]]; // Vincenzo Librandi, Mar 18 2020
(Python)
def a(n): return (n**4 + 18*n**3 + 83*n**2 + 114*n)//24
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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