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A076008
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Second column of triangle A075504.
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2
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1, 27, 567, 10935, 203391, 3720087, 67493007, 1219657095, 21996874431, 396331160247, 7137447668847, 128505439098855, 2313380333315871, 41643387865514007, 749603858371707087, 13493075341822822215
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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..1).
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FORMULA
| a(n)=A075504(n+2, 2)=(9^n)*S2(n+2, 2) with S2(n, m) := A008277(n, m) (Stirling2).
a(n)= -9^n+2*18^n.
G.f.: 1/((1-9*x)*(1-18*x)).
E.g.f.: diff((((exp(9*x)-1)/9)^2)/2!, x$2) = -exp(9*x)+2*exp(18*x).
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CROSSREFS
| Cf. A001019, A076009.
Sequence in context: A051561 A163197 A061914 * A185891 A185883 A099753
Adjacent sequences: A076005 A076006 A076007 * A076009 A076010 A076011
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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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