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A093344
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n! * Sum_{i=1..n} (1/i)*Sum_{j=0..i-1} 1/j!.
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4
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0, 1, 4, 17, 84, 485, 3236, 24609, 210572, 2004749, 21033900, 241237001, 3003349124, 40345599957, 581765196884, 8963453118065, 146969877361116, 2555361954692189, 46963373856864092, 909707559383702169
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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FORMULA
| E.g.f.: exp(1)*(Ei(1,1-x)-Ei(1,1))/(1-x). - Vladeta Jovovic (vladeta(AT)eunet.rs), May 05 2007
a(n)=int(exp(1-x)*(x^n*ln(x)-n!/x),x=1..infinity) - Roland Groux, Mar 12 2011.
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PROG
| (PARI) a(n)=n!*sum(i=1, n, 1/i*sum(j=0, i-1, 1/j!))
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CROSSREFS
| Cf. A000254, A000774.
Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), Oct 16 2009: (Start)
Equals for n=>1 the row sums of A165674 and A093905.
(End)
Sequence in context: A052315 A200716 A093904 * A087316 A104979 A081052
Adjacent sequences: A093341 A093342 A093343 * A093345 A093346 A093347
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KEYWORD
| nonn
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AUTHOR
| Ralf Stephan, Apr 26 2004
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