OFFSET
1,1
COMMENTS
The third row of the array A059503.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (6,-11,6,-1).
FORMULA
From Colin Barker, Nov 30 2012: (Start)
a(n) = 6*a(n-1) - 11*a(n-2) + 6*a(n-3) - a(n-4).
G.f.: x*(1-x)*(2*x^2-8*x+3)/(x^2-3*x+1)^2. (End)
a(n) = ((3 - n)*Fibonacci(2*n) + (10 + 3*n)*Fibonacci(2*n - 1))/5. - G. C. Greubel, Sep 10 2017
MATHEMATICA
LinearRecurrence[{6, -11, 6, -1}, {3, 7, 19, 53}, 30] (* Harvey P. Dale, Jul 30 2015 *)
Rest[CoefficientList[Series[x*(1 - x)*(2*x^2 - 8*x + 3)/(x^2 - 3*x + 1)^2, {x, 0, 50}], x]] (* G. C. Greubel, Sep 10 2017 *)
PROG
(PARI) Vec(x*(1-x)*(2*x^2-8*x+3)/(x^2-3*x+1)^2 + O(x^30)) \\ Michel Marcus, Sep 09 2017
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Floor van Lamoen, Jan 19 2001
STATUS
approved