OFFSET
0,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
R. Sachdeva and A. K. Agarwal, Combinatorics of certain restricted n-color composition functions, Discrete Mathematics, 340, (2017), 361-372. See sequence C_4.
Index entries for linear recurrences with constant coefficients, signature (0,4,1,-1).
MATHEMATICA
CoefficientList[Series[x (2+x)/(1-4x^2-x^3+x^4), {x, 0, 40}], x] (* or *) LinearRecurrence[{0, 4, 1, -1}, {0, 2, 1, 8}, 40] (* Harvey P. Dale, May 14 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jan 16 2017
STATUS
approved