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1, 9, 90, 990, 11880, 154440, 2162160, 32432400, 518918400, 8821612800, 158789030400, 3016991577600, 60339831552000, 1267136462592000, 27877002177024000, 641171050071552000, 15388105201717248000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| The asymptotic expansion of the higher order exponential integral E(x,m=1,n=9) ~ exp(-x)/x*(1 - 9/x + 90/x^2 - 990/x^3 + 11880/x^4 - 154440/x^5 + ...) leads to the sequence given above. See A163931 and A130534 for more information. [Johannes W. Meijer, Oct 20 2009]
a(n) = A173333(n+8,8). [From Reinhard Zumkeller, Feb 19 2010]
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..300
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FORMULA
| a(n) = (n+8)!/8!; e.g.f.: 1/(1-x)^9.
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PROG
| (MAGMA) [Factorial(n+8)/40320: n in [0..25]]; // Vincenzo Librandi, Jul 20 2011
(PARI) a(n) = (n+8)!/8!;
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CROSSREFS
| Cf. A000142, A001710, A001715, A001720, A001725, A001730, A049388, A051379. a(n)= A051380(n, 0)*(-1)^n (first unsigned column of triangle).
Sequence in context: A143079 A165324 A082367 * A127769 A062815 A160569
Adjacent sequences: A049386 A049387 A049388 * A049390 A049391 A049392
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KEYWORD
| easy,nonn
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)
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