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A153647
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a(n) = 3^n*(n + 2)!.
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2
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2, 18, 216, 3240, 58320, 1224720, 29393280, 793618560, 23808556800, 785682374400, 28284565478400, 1103098053657600, 46330118253619200, 2084855321412864000, 100073055427817472000, 5103725826818691072000, 275601194648209317888000
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OFFSET
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0,1
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LINKS
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FORMULA
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G.f.: 2*Hypergeometric2F0([1, 3]; --; 3*x).
E.g.f.: 2/(1-3*x)^3. (End)
D-finite with recurrence a(n) +3*(-n-2)*a(n-1)=0. - R. J. Mathar, Aug 20 2021
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MAPLE
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MATHEMATICA
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Table[3^n*(n + 2)!, {n, 0, 30}]
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PROG
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(Sage) [3^n*factorial(n+2) for n in (0..20)] # G. C. Greubel, Mar 03 2021
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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