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A131446
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Denominators of n-th approximation of factorial (also called harmonic) expansion of Pi.
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1
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1, 1, 1, 8, 15, 720, 5040, 13440, 13440, 3628800, 532224, 43545600, 691891200, 691891200, 108972864000, 1902071808000, 118562476032000, 6847458508800, 24329020081766400, 17888985354240000, 1344498478202880000
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OFFSET
| 1,4
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COMMENTS
| Numerators are given in A131445.
For the rationals r(n) and some values see the W. Lang link under A131445.
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FORMULA
| a(n)=denominator(r(n)), with r(n):=sum(b(k)/k!,n=1..n) with b(k):=A075874(k) (factorial expansion of Pi).
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EXAMPLE
| Rationals r(n): [3,3,3,25/8,47/15,2261/720,15833/5040,42223/13440,42223/13440,...].
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CROSSREFS
| Sequence in context: A153700 A190901 A066916 * A061746 A028585 A073926
Adjacent sequences: A131443 A131444 A131445 * A131447 A131448 A131449
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KEYWORD
| nonn,frac,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Aug 07 2007
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