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A155179
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a(n)=4*a(n-1)+a(n-2), n>2; a(0)=1, a(1)=3, a(2)=12.
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2
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1, 3, 12, 51, 216, 915, 3876, 16419, 69552, 294627, 1248060, 5286867, 22395528, 94868979, 401871444, 1702354755, 7211290464, 30547516611, 129401356908, 548152944243, 2322013133880, 9836205479763, 41666835052932
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1-x-x^2)/((1-4*x-x^2).
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MATHEMATICA
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Clear[f, lst, n, a] f[n_]:=Fibonacci[n]; lst={}; Do[a=f[n]*(3/2); If[IntegerQ[a], AppendTo[lst, a]], {n, 0, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 25 2009 *)
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PROG
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(PARI) concat(1, select(n->denominator(n)==1, [fibonacci(n)*3/2|n<-[1..50]])) \\ Charles R Greathouse IV, Dec 09 2014
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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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