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A069015
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a(n) = n! * 3^n * Sum_{i=1..n} 1/(i * 3^i).
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2
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1, 7, 65, 786, 11814, 212772, 4468932, 107259408, 2896044336, 86881692960, 2867099496480, 103215621790080, 4025409728814720, 169067214837239040, 7608024754854048000, 365185189540668672000, 18624444687496892160000
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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Rest[CoefficientList[Series[-Log[1-x]/(1-3*x), {x, 0, 20}], x]* Range[0, 20]!] (* Vaclav Kotesovec, Oct 05 2013 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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