OFFSET
0,1
COMMENTS
The o.g.f. S(x) for A001003 (Schroeder II) satisfies 2*S^2(x) + (1+x)*S(x) + x = 0.
LINKS
FORMULA
G.f.: x*(1-2*x)/(1-x).
a(0) = 0, a(1) = 1, a(n) = -1, n >= 2.
E.g.f.: 1 + 2*x - exp(x). - Elmo R. Oliveira, Dec 23 2025
MATHEMATICA
PadRight[{0, 1}, 100, -1] (* Paolo Xausa, Mar 03 2026 *)
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Wolfdieter Lang, Nov 13 2007
STATUS
approved
