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A137247
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a(n)=4a(n-1)-6a(n-2)+6a(n-3)-3a(n-4).
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0
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0, 0, 0, 1, 4, 10, 22, 49, 112, 256, 580, 1309, 2956, 6682, 15106, 34141, 77152, 174352, 394024, 890473, 2012404, 4547866, 10277806, 23227033, 52491280, 118626160, 268085740, 605852581, 1369179004, 3094236490, 6992730202, 15803018149
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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COMMENTS
| Essentially the partial sums of A052103. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 01 2008
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FORMULA
| O.g.f.: x^3/[(x-1)(3*x^3-3*x^2+3*x-1)]. A052103(n)=a(n+2)-a(n+1). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 01 2008
a(n)=-(1/2)+(1/6)*{1+[(1/2)*I]*108^(1/6)-(1/2)*2^(1/3)}^n+(1/6)*[1-(1/2)*I]*108^(1/6)-(1/2)*2^(1 /3))^n+(1/6)*[1+2^(1/3)]^n, with n>=0 and I=sqrt(-1) - Paolo P. Lava (paoloplava(AT)gmail.com), Jun 09 2008
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MAPLE
| a[0]:=0: a[1]:=0: a[2]:=0: a[3]:=1: for n from 4 to 30 do a[n]:=4*a[n-1]-6*a[n-2]+6*a[n-3]-3*a[n-4] end do: seq(a[n], n=0..30); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 17 2008
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CROSSREFS
| Sequence in context: A056112 A118430 A178452 * A155407 A124697 A155426
Adjacent sequences: A137244 A137245 A137246 * A137248 A137249 A137250
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KEYWORD
| nonn,easy
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AUTHOR
| Paul Curtz (bpcrtz(AT)free.fr), Mar 10 2008
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Rolf Pleisch (r_pleisch(AT)gmx.ch) and Emeric Deutsch (deutsch(AT)duke.poly.edu), Apr 01 2008
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