OFFSET
0,1
LINKS
FORMULA
G.f.: ((1-x)(2-4x))/(1-4x-5x^2). For n>0: a(n)=4*5^(n-1)+2(-1)^n
MATHEMATICA
CoefficientList[Series[((1 - x)(2 - 4x))/(1 - 4x - 5x^2), {x, 0, 25}], x]
LinearRecurrence[{4, 5}, {2, 2, 22}, 30] (* Harvey P. Dale, Oct 23 2024 *)
CROSSREFS
KEYWORD
easy,nonn,changed
AUTHOR
Mario Catalani (mario.catalani(AT)unito.it), Sep 01 2003
STATUS
approved