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A273060
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a(n) = phi(n!)/phi(n).
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1
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1, 1, 1, 4, 8, 96, 192, 2304, 13824, 207360, 829440, 24883200, 99532800, 2786918400, 31352832000, 501645312000, 4013162496000, 192631799808000, 1155790798848000, 52010585948160000, 728148203274240000, 19223112566439936000, 192231125664399360000
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OFFSET
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1,4
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LINKS
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FORMULA
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MAPLE
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seq(numtheory:-phi(n!)/numtheory:-phi(n), n=1..50); # Robert Israel, Nov 13 2016
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MATHEMATICA
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Table[EulerPhi[n!]/EulerPhi[n], {n, 1, 25}] (* G. C. Greubel, Oct 30 2016 *)
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PROG
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(Magma) [EulerPhi(Factorial(n)) div EulerPhi(n): n in [1..25]]; // Vincenzo Librandi, Oct 30 2016
(PARI) a(n) = eulerphi(n!)/eulerphi(n); \\ Michel Marcus, Oct 30 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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