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A014336
Three-fold exponential convolution of Fibonacci numbers with themselves.
2
0, 0, 0, 6, 36, 210, 1080, 5460, 26964, 132294, 645480, 3142590, 15277680, 74222616, 360445176, 1750067430, 8496115740, 41243946330, 200209950504, 971859585804, 4717557894060, 22899644483430, 111157568501760
OFFSET
0,4
FORMULA
(1/5)(3^n*Fibonacci(n) - 3*Fibonacci(2n)). - Ralf Stephan, May 14 2004
From R. J. Mathar, Jun 10 2013: (Start)
G.f.: -6*x^3 / ( (x^2-3*x+1)*(9*x^2+3*x-1) ).
a(n) = 6*A014337(n). (End)
MAPLE
with(combinat):A014336:=proc(n)return (1/5)*(3^n*fibonacci(n)-3*fibonacci(2*n)):end:
seq(A014336(n), n=0..22); # Nathaniel Johnston, Apr 18 2011
PROG
(Magma) [(1/5)*(3^n*Fibonacci(n) - 3*Fibonacci(2*n)): n in [0..30]]; // Vincenzo Librandi, Apr 18 2011
CROSSREFS
Cf. A000045.
Sequence in context: A064238 A354229 A354231 * A268941 A269637 A269534
KEYWORD
nonn,easy
STATUS
approved