OFFSET
0,1
LINKS
FORMULA
a(n) = 6*n - a(n-1) - 2 (with a(0)=3). - Vincenzo Librandi, Nov 24 2010
From Chai Wah Wu, Jul 28 2020: (Start)
a(n) = a(n-1) + a(n-2) - a(n-3) for n > 2.
G.f.: (5*x^2 - 2*x + 3)/((x - 1)^2*(x + 1)). (End)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Mar 25 2008
STATUS
approved