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A034834
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One seventh of sept-factorial numbers.
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11
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1, 14, 294, 8232, 288120, 12101040, 592950960, 33205253760, 2091930986880, 146435169081600, 11275508019283200, 947142673619788800, 86189983299400780800, 8446618363341276518400, 886894928150834034432000, 99332231952893411856384000, 11820535602394316010909696000
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OFFSET
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1,2
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LINKS
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G. C. Greubel, Table of n, a(n) for n = 1..335
Index entries for sequences related to factorial numbers.
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FORMULA
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7*a(n) = (7*n)(!^7) = Product_{j=1..n} 7*j = 7^n*n!.
E.g.f.: x/(1-7*x).
a(n) = A051188(n)/7.
From Amiram Eldar, Jan 08 2022: (Start)
Sum_{n>=1} 1/a(n) = 7*(exp(1/7)-1).
Sum_{n>=1} (-1)^(n+1)/a(n) = 7*(1-exp(-1/7)). (End)
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MATHEMATICA
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Table[7^(n-1)*n!, {n, 1, 30}] (* or *) Drop[With[{nn = 50}, CoefficientList[ Series[x/(1-7*x), {x, 0, nn}], x]*Range[0, nn]!], 1] (* G. C. Greubel, Feb 22 2018 *)
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PROG
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(PARI) my(x='x+O('x^30)); Vec(serlaplace(x/(1-7*x))) \\ G. C. Greubel, Feb 22 2018
(Magma) [7^(n-1)*Factorial(n): n in [1..30]]; // G. C. Greubel, Feb 22 2018
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CROSSREFS
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Cf. A045754, A034829, A034830, A034831, A034832, A034833, A051188.
Sequence in context: A158475 A116165 A186376 * A276699 A258491 A251220
Adjacent sequences: A034831 A034832 A034833 * A034835 A034836 A034837
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KEYWORD
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easy,nonn
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AUTHOR
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Wolfdieter Lang
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EXTENSIONS
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More terms from G. C. Greubel, Feb 22 2018
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STATUS
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approved
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