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Search: id:A084059
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| A084059 |
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a(n)=4a(n-1)+2a(n-2), a(0)=1,a(1)=2. |
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+0
3
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| 1, 2, 10, 44, 196, 872, 3880, 17264, 76816, 341792, 1520800, 6766784, 30108736, 133968512, 596091520, 2652303104, 11801395456, 52510188032, 233643543040, 1039594548224, 4625665278976, 20581850212352, 91578731407360
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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Binomial transform of A002533.
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FORMULA
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E.g.f.: exp(2x)cosh(sqrt(6)x).
a(n)=((2+sqrt(6))^n+(2-sqrt(6))^n)/2. - Paul Barry (pbarry(AT)wit.ie), May 13 2003
a(n)=sum{k=0..floor(n/2), C(n,2k)*2^(n-k)*3^k}; - Paul Barry (pbarry(AT)wit.ie), Jan 15 2007
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CROSSREFS
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Sequence in context: A068551 A099919 A100397 this_sequence A084609 A105485 A065805
Adjacent sequences: A084056 A084057 A084058 this_sequence A084060 A084061 A084062
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KEYWORD
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easy,nonn
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AUTHOR
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Paul Barry (pbarry(AT)wit.ie), May 10 2003
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