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A107361
G.f. 1/((3*x-1)*(x^2-x-1)).
0
1, 2, 8, 21, 68, 196, 601, 1782, 5380, 16085, 48344, 144888, 434897, 1304314, 3913552, 11739669, 35220604, 105659228, 316981865, 950938830, 2852827436, 8558464597, 25675422448, 77026220976, 231078737953, 693236092466
OFFSET
0,2
FORMULA
a(n) = (1/11)*[A000244(n+2) + (-1)^n*A001060(n)].
a(0)=1, a(1)=2, a(n) = (1/11)*[3^(n+2) + (-1)^n*{Fib(n+4)-Fib(n-1)}], Fib(n) = A000045(n). -- Ralf Stephan, Nov 27 2010
a(0)=1, a(1)=2, a(2)=8, a(n)=2*a(n-1)+4*a(n-2)-3*a(n-3). - Harvey P. Dale, Jan 24 2015
MAPLE
with(gfun): seriestolist(series(1/((3*x-1)*(x^2-x-1)), x=0, 32));
MATHEMATICA
LinearRecurrence[{2, 4, -3}, {1, 2, 8}, 30] (* Harvey P. Dale, Jan 24 2015 *)
CROSSREFS
Sequence in context: A143212 A316270 A219970 * A185309 A318040 A333705
KEYWORD
nonn,easy
AUTHOR
Creighton Dement, May 23 2005
STATUS
approved