OFFSET
0,1
COMMENTS
a(n) = T(n, 3), array T as in A049627.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,1,1,0,-1).
FORMULA
G.f.: 2 - x*(-6-8*x-4*x^2+2*x^3+3*x^4) / ( (1+x)*(1+x+x^2)*(x-1)^2 ). - R. J. Mathar, Oct 26 2015
MATHEMATICA
CoefficientList[Series[2 - x*(-6 - 8*x - 4*x^2 + 2*x^3 + 3*x^4)/((1 + x)*(1 + x + x^2)*(x - 1)^2), {x, 0, 50}], x] (* G. C. Greubel, Dec 15 2017 *)
LinearRecurrence[{0, 1, 1, 0, -1}, {2, 6, 8, 10, 12, 15}, 70] (* Harvey P. Dale, Apr 21 2019 *)
PROG
(PARI) x='x+O('x^30); Vec(2 - x*(-6 - 8*x - 4*x^2 + 2*x^3 + 3*x^4)/((1 + x)*(1 + x + x^2)*(x - 1)^2)) \\ G. C. Greubel, Dec 15 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Terms a(38) onward added by G. C. Greubel, Dec 15 2017
STATUS
approved