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A076009
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Third column of triangle A075504.
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2
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1, 54, 2025, 65610, 1974861, 57041334, 1607609025, 44625100770, 1226874595221, 33521945231214, 912229968911625, 24758714599712730, 670798674525559581, 18153207600055622694, 490886209059873519825
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OFFSET
| 0,2
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COMMENTS
| The e.g.f. given below is sum(A075513(3,m)*exp(9*(m+1)*x),m=0..2)/2!.
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FORMULA
| a(n)=A075504(n+3, 3)=(9^n)*S2(n+3, 3) with S2(n, m) := A008277(n, m) (Stirling2).
a(n)= (9^n-8*18^n+9*27^n)/2.
G.f.: 1/product(1-9*k*x, k=1..3).
E.g.f.: diff((((exp(9*x)-1)/9)^3)/3!, x$3) = (exp(9*x)-8*exp(18*x)+9*exp(27*x))/2!.
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CROSSREFS
| Cf. A076008, A076010.
Sequence in context: A173188 A004363 A062144 * A003755 A174445 A206940
Adjacent sequences: A076006 A076007 A076008 * A076010 A076011 A076012
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KEYWORD
| nonn,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Oct 02, 2002
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