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A267141
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Number of weeks in n! seconds, for n >= 10.
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0
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6, 66, 792, 10296, 144144, 2162160, 34594560, 588107520, 10585935360, 201132771840, 4022655436800, 84475764172800, 1858466811801600, 42744736671436800, 1025873680114483200, 25646842002862080000, 666817892074414080000
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OFFSET
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10,1
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COMMENTS
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10! seconds = 6 weeks (exactly)
11! seconds = 66 weeks (exactly)
12! seconds = 792 weeks (exactly), etc.
Demonstration of first term:
6 w * 7 d/w * 24 h/d * 60 m/h * 60 s/m = seconds in 6 weeks =
(2*3)*(1*7) *(3*8) * (6*10) * (3*5*4) =
1*2*3*4*5*6*7*8*(3^2)*10 = 10! seconds
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LINKS
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Table of n, a(n) for n=10..26.
Brady Haran, James Grime, 10!, Numberphile video (2012)
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FORMULA
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a(n) = 6*n!/10!.
a(n) = 6*A051431(n-10), for n>=10.
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EXAMPLE
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For n=12, a(12) = 6*(12)!/10! = 792; interpretation: 12! seconds = 792 weeks.
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MATHEMATICA
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f[n_] := n!/(60*60*24*7); Array[f, 17, 10] (* Robert G. Wilson v, Jan 12 2016 *)
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PROG
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(PARI) a(n) = 6*n!/10!; \\ Altug Alkan, Jan 12 2016
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CROSSREFS
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Cf. A051431.
Sequence in context: A127857 A127858 A173535 * A004355 A282046 A124862
Adjacent sequences: A267138 A267139 A267140 * A267142 A267143 A267144
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KEYWORD
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easy,nonn
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AUTHOR
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Richard H. Sweetman, Jan 10 2016
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STATUS
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approved
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