OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (3,1,-7,0,4).
FORMULA
a(n) = ((n + 1)*2^(n + 2) - 3 + (4*n + 1)*(-1)^(n + 1))/6.
G.f.: (4*x^3 - 2*x^2 + 3*x - 3)*x/((-1 + 2*x)^2*(-1 + x)*(1 + x)^2).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Petros Hadjicostas, Feb 15 2021
STATUS
approved