OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..10000
Index entries for linear recurrences with constant coefficients, signature (1,2,-2,-1,1).
FORMULA
a(0)=1, a(1)=2, a(n)=(n-1)*(n+(-1)^n), n>1.
G.f.: -(2*x^6-10*x^4+x^3+x^2-x-1)/((1-x)^3*(1+x)^2). [Colin Barker, Sep 03 2012]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Barry, Mar 19 2003
STATUS
approved