OFFSET
0,4
LINKS
Index entries for linear recurrences with constant coefficients, signature (1,0,1,-1,0,1,-1,0,-1,1).
FORMULA
a(n) = a(n-1)+a(n-3)-a(n-4)+a(n-6)-a(n-7)-a(n-9)+a(n-10).
G.f.: (4*x^3 + 2*x^4 + x^5 + 7*x^6 + x^7 + 2*x^8 + x^9)/(1 - x - x^3 + x^4 - x^6 + x^7 + x^9 - x^10).
MATHEMATICA
a[n_] := Floor[(3 n/2)*Floor[n/3]]
Table[a[n], {n, 0, 90}] (* A213034 *)
LinearRecurrence[{1, 0, 1, -1, 0, 1, -1, 0, -1, 1}, {0, 0, 0, 4, 6, 7, 18, 21, 24, 40}, 90]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 05 2012
STATUS
approved