OFFSET
0,2
COMMENTS
Linear recurrence and g.f. confirmed by Shutov/Maleev link in A301670. - Ray Chandler, Aug 30 2023
LINKS
Ray Chandler, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0, 1, 1, 1, -1, -1, -1, 0, 1).
FORMULA
From Chai Wah Wu, Mar 11 2021: (Start)
a(n) = a(n-2) + a(n-3) + a(n-4) - a(n-5) - a(n-6) - a(n-7) + a(n-9) for n > 9.
G.f.: (2*x^9 - x^8 - 5*x^7 - 16*x^6 - 21*x^5 - 22*x^4 - 19*x^3 - 12*x^2 - 5*x - 1)/((x - 1)^3*(x + 1)^2*(x^2 + 1)*(x^2 + x + 1)). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 25 2018
STATUS
approved