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A020976
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Expansion of 1/((1-8*x)*(1-9*x)*(1-10*x)).
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1
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1, 27, 487, 7335, 99631, 1265607, 15341887, 179688375, 2050086511, 22913907687, 251930201887, 2733012078615, 29322230800591, 311701053949767, 3287717299503487, 34448718207176055, 358912563957741871
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OFFSET
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0,2
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LINKS
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FORMULA
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If we define f(m,j,x)=sum(binomial(m,k)*stirling2(k,j)*x^(m-k),k=j..m) then a(n-2)=f(n,2,8), (n>=2). - Milan Janjic, Apr 26 2009
a(0) = 1, a(1) = 27, a(2) = 487, a(n) = 27*a(n-1)-242*a(n-2)+720*a(n-3).
a(n) = 2^(2+3*(n+1))+2^(n+1)*5^(2+n)-9^(2+n). (End)
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MAPLE
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a:=seq(2^(2+3*(n+1))+2^(n+1)*5^(2+n)-9^(2+n), n=0..16); # Muniru A Asiru, Feb 10 2018
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MATHEMATICA
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CoefficientList[Series[1/((1-8x)(1-9x)(1-10x)), {x, 0, 20}], x] (* or *)
LinearRecurrence[{27, -242, 720}, {1, 27, 487}, 20] (* or *)
Table[2^(3n+2)+ 2^n 5^(n+1)- 9^(n+1), {n, 20}] (* Harvey P. Dale, Oct 25 2011 *)
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PROG
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(Magma) [2^(2+3*(n+1))+2^(n+1)*5^(n+2)-9^(n+2): n in [0..30]]; // Vincenzo Librandi, Oct 26 2011
(PARI) x='x+O('x^30); Vec(1/((1-8*x)*(1-9*x)*(1-10*x))) \\ G. C. Greubel, Feb 09 2018
(GAP) a:=[1, 27, 487];; for n in [4..17] do a[n]:=27*a[n-1]-242*a[n-2]+720*a[n-3]; od; # Muniru A Asiru, Feb 10 2018
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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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EXTENSIONS
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STATUS
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approved
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