OFFSET
0,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
W. Lang, Riccati meets Fibonacci, The Fibonacci Quarterly, 42 (2004) pp. 231-244, eqs.(58),(59).
Index entries for linear recurrences with constant coefficients, signature (12, -36, -16, 96, 0, -64).
FORMULA
G.f.: 1/(1-6*x+8*x^3)^2.
a(n) = (2*(n+1)*b(n+1)-(n+3)*b(n)-4*(n+2)*b(n-1))/9, with b(n):=A111989(n).
MATHEMATICA
CoefficientList[Series[1/(1-6x+8x^3)^2, {x, 0, 30}], x] (* or *) LinearRecurrence[{12, -36, -16, 96, 0, -64}, {1, 12, 108, 848, 6192, 43200}, 30] (* Harvey P. Dale, Dec 07 2022 *)
PROG
(PARI) Vec(1/(1-6*x+8*x^3)^2 + O(x^30)) \\ Michel Marcus, Mar 11 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Sep 12 2005
STATUS
approved