OFFSET
0,6
LINKS
Index entries for linear recurrences with constant coefficients, signature (2,-1,0,0,0,0,0,0,1,-2,1).
FORMULA
From R. J. Mathar, Apr 15 2010: (Start)
G.f.: x^4*(1 + x^4)/ ((1 - x)^3*(1 + x + x^2)*(1 + x^3 + x^6)).
a(n) = 2*a(n-1) - a(n-2) + a(n-9) - 2*a(n-10) + a(n-11). (End)
MATHEMATICA
Table[Floor[(n(n-1))/9], {n, 0, 70}] (* or *) LinearRecurrence[{2, -1, 0, 0, 0, 0, 0, 0, 1, -2, 1}, {0, 0, 0, 0, 1, 2, 3, 4, 6, 8, 10}, 70] (* Harvey P. Dale, Oct 01 2017 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved