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A165206
a(n) = (3-4*n)*F(2*n-2) + (4-7*n)*F(2*n-1).
2
1, -3, -25, -112, -416, -1411, -4537, -14085, -42653, -126794, -371554, -1076423, -3089555, -8799207, -24897121, -70052356, -196151492, -546916555, -1519249933, -4206274089, -11611243109, -31967026718, -87796880710
OFFSET
0,2
COMMENTS
Hankel transform of A165205.
FORMULA
G.f.: (1-9*x+4*x^2-x^3)/(1-3*x+x^2)^2 = (1-x)/(1-3*x+x^2) - 5*x/(1-3*x+x^2)^2.
a(n) = -5*A001871(n-1) + A001519(n+1). - R. J. Mathar, Dec 16 2024
MATHEMATICA
Table[(3-4n)Fibonacci[2n-2]+(4-7n)Fibonacci[2n-1], {n, 0, 30}] (* or *) LinearRecurrence[{6, -11, 6, -1}, {1, -3, -25, -112}, 30] (* Harvey P. Dale, Aug 25 2013 *)
PROG
(PARI) vector(30, n, n--; f=fibonacci; (3-4*n)*f(2*n-2)+(4-7*n)*f(2*n-1)) \\ G. C. Greubel, Jul 18 2019
(Magma) F:=Fibonacci; [(3-4*n)*F(2*n-2)+(4-7*n)*F(2*n-1): n in [0..30]]; // G. C. Greubel, Jul 18 2019
(Sage) f=fibonacci; [(3-4*n)*f(2*n-2)+(4-7*n)*f(2*n-1) for n in (0..30)] # G. C. Greubel, Jul 18 2019
(GAP) F:=Fibonacci;; List([0..30], n-> (3-4*n)*F(2*n-2)+(4-7*n)*F(2*n-1) ); # G. C. Greubel, Jul 18 2019
CROSSREFS
Cf. A000045.
Sequence in context: A166899 A201534 A059457 * A095664 A215773 A377555
KEYWORD
easy,sign
AUTHOR
Paul Barry, Sep 07 2009
STATUS
approved