OFFSET
4,1
LINKS
R. H. Hardin, Table of n, a(n) for n=4..500
Index entries for linear recurrences with constant coefficients, signature (2,0,-1,-1,2,-1).
FORMULA
G.f.: -x^4*(-13+5*x+8*x^2+2*x^3-12*x^4+8*x^5) / ( (x-1)*(x^5-x^4+x^2+x-1) ). - R. J. Mathar, Jan 19 2011
a(n) = 2*a(n-1)-a(n-3)-a(n-4)+2*a(n-5)-a(n-6). - Wesley Ivan Hurt, Jan 16 2022
MATHEMATICA
LinearRecurrence[{2, 0, -1, -1, 2, -1}, {13, 21, 34, 53, 84, 131}, 50] (* Harvey P. Dale, Jul 03 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 14 2009
STATUS
approved