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A141055
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The n-th differences of the row A141045(n,.).
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1
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-1, -2, -60, -120, -5040, -10080, -302400, -604800, -39916800, -79833600, -217945728000, -435891456000, -2615348736000, -5230697472000, -2667655710720000, -5335311421440000, -4257578514309120000, -8515157028618240000, -2810001819444019200000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Can be thought of as the second sequence of a family: the first is A091137, the third starts 1, 2, 84, 168.
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FORMULA
| a(n+1)=a(n)*A027760(n+3).
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EXAMPLE
| The first differences of A141045(2,.) are 11-(-19)=30 and -19-11 = -30. The 2nd difference is a(2)= -30-30= -60.
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PROG
| (PARI) a(n)=if(n, my(pr=a(n-1)); fordiv(n+2, d, if(isprime(d+1), pr*=d+1)); pr, -1) \\ Charles R Greathouse IV, Jul 08 2011
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CROSSREFS
| Sequence in context: A113549 A117482 A078511 * A048541 A067739 A187626
Adjacent sequences: A141052 A141053 A141054 * A141056 A141057 A141058
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KEYWORD
| sign,uned
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AUTHOR
| Paul Curtz (bpcrtz(AT)free.fr), Aug 01 2008
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EXTENSIONS
| Edited and extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 12 2008
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