OFFSET
0,3
LINKS
Paolo Xausa, Table of n, a(n) for n = 0..1000
Lara Pudwell, Systematic Studies in Pattern Avoidance, 2005.
Index entries for linear recurrences with constant coefficients, signature (2,0,0,-1).
FORMULA
G.f.: (x^5 + 3*x^4 + x^3 - x+1)/((x-1)*(x^3 + x^2 + x - 1)).
MAPLE
MATHEMATICA
LinearRecurrence[{2, 0, 0, -1}, {1, 1, 2, 5, 12, 24}, 50] (* Paolo Xausa, Jan 19 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Lara Pudwell, Feb 26 2006
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, Jan 19 2024
STATUS
approved