OFFSET
0,2
COMMENTS
Binomial transform of A052948.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (6,-9,2).
FORMULA
a(0)=1, a(2)=2, a(2)=6, a(n) = 6*a(n-1)-9*a(n-2)+2*a(n-3), n>2.
a(n) = (2^n+(2+sqrt(3))^n+(2-sqrt(3))^n)/3.
MATHEMATICA
CoefficientList[Series[(1-4x+3x^2)/((1-2x)(1-4x+x^2)), {x, 0, 30}], x] (* or *) LinearRecurrence[{6, -9, 2}, {1, 2, 6}, 30] (* Harvey P. Dale, Feb 09 2013 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Sep 16 2003
STATUS
approved