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A083582
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(8*2^n-5*(-1)^n)/3.
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4
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1, 7, 9, 23, 41, 87, 169, 343, 681, 1367, 2729, 5463, 10921, 21847, 43689, 87383, 174761, 349527, 699049, 1398103, 2796201, 5592407, 11184809, 22369623, 44739241, 89478487, 178956969, 357913943, 715827881, 1431655767, 2863311529
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Binomial transform of A083582
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..1000
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FORMULA
| a(n)=(8*2^n-5(-1)^n)/3 G.f. (1+6x)/((1-2x)(1+x)) E.g.f. (8exp(2x)-5exp(-x))/3
a(n) = 6*A001045(n) + A001045(n+1) - Creighton Dement (creighton.k.dement(AT)uni-oldenburg.de), Mar 25 2005
a(n) = 2^(n+2)th coefficient of - eta(z)^3 eta(z^5) eta(z^10)^2 /eta(z^2)^2 - Kok Seng Chua (chuaks(AT)ihpc.a-star.edu.sg), Aug 30 2005
a(n)=a(n-1)+2a(n-2). a(n)+a(n+1)=8*A000079 =a(n+2)-a(n). - Paul Curtz (bpcrtz(AT)free.fr), Jul 27 2008
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MAPLE
| BB := n->if n=1 then 3; > elif n=2 then 1; > else 2*BB(n-2)+BB(n-1); > fi: > L:=[]: for k from 2 to 32 do L:=[op(L), BB(k)]: od: L; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 19 2007
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MATHEMATICA
| f[n_]:=2/(n+1); x=6; Table[x=f[x]; Denominator[x], {n, 0, 5!}] [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Mar 12 2010]
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PROG
| (MAGMA) [(8*2^n-5*(-1)^n)/3: n in [0..30]]; // Vincenzo Librandi, Aug 13 2011
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CROSSREFS
| Sequence in context: A070423 A018882 A179788 * A029633 A049301 A102028
Adjacent sequences: A083579 A083580 A083581 * A083583 A083584 A083585
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KEYWORD
| easy,nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), May 01 2003
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