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A289830
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a(n) satisfies the equation n/(n-1) + a(n)/n! = H(n), where H(n) is the n-th harmonic number.
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0
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-1, 2, 18, 124, 900, 7188, 63504, 618336, 6596640, 76635360, 963895680, 13056819840, 189581333760, 2938083321600, 48416639846400, 845487698227200, 15598004134809600, 303161985274982400, 6191998554470400000, 132599321499875328000, 2970952207377960960000
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OFFSET
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2,2
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LINKS
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FORMULA
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MATHEMATICA
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Table[n!*(HarmonicNumber[n] - n/(n - 1)), {n, 2, 22}] (* Michael De Vlieger, Jul 13 2017 *)
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PROG
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(Python)
from sympy import factorial, harmonic
def a(n): return factorial(n-2)*(harmonic(n)*(n-1) - n)*n
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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