OFFSET
2,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 2..1000
Index entries for linear recurrences with constant coefficients, signature (7,-19,26,-19,7,-1).
FORMULA
G.f.: x^2*(1+9*x-x^2-x^3) / ((1-x)^4*(1-3*x+x^2)). - Colin Barker, Dec 10 2015
a(n) = Fibonacci(2*n+5) - (4*n^3 + 6*n^2 + 14*n + 15)/3. - G. C. Greubel, Sep 28 2019
MAPLE
with(combinat); seq(fibonacci(2*n+5) - (4*n^3 +6*n^2 +14*n +15)/3, n=2..30); # G. C. Greubel, Sep 28 2019
MATHEMATICA
Table[Fibonacci[2*n+5] -(4*n^3 +6*n^2 +14*n +15)/3, {n, 2, 30}] (* G. C. Greubel, Sep 28 2019 *)
PROG
(PARI) vector(30, n, my(m=n+1); fibonacci(2*m+5) - (4*m^3 +6*m^2 +14*m +15)/3) \\ G. C. Greubel, Sep 28 2019
(Magma) [Fibonacci(2*n+5) - (4*n^3 +6*n^2 +14*n +15)/3: n in [2..30]]; // G. C. Greubel, Sep 28 2019
(Sage) [fibonacci(2*n+5) - (4*n^3 +6*n^2 +14*n +15)/3 for n in (2..30)] # G. C. Greubel, Sep 28 2019
(GAP) List([2..30], n-> Fibonacci(2*n+5) - (4*n^3 +6*n^2 +14*n +15)/3 ); # G. C. Greubel, Sep 28 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved