OFFSET
0,2
LINKS
FORMULA
a(n) = a(n-1) - 3*a(n-2) + 3*a(n-3), for n >= 5.
E.g.f.: (1/3)*( 2 + 2*x - 3*exp(x) + 4*cosh(sqrt(3)*x) + (7/sqrt(3))*sinh(sqrt(3)*x) ).
G.f.: (1 +x -2*x^2 +2*x^4)/((1-x)*(1-3*x^2)). - Clark Kimberling, Oct 31 2022
MATHEMATICA
LinearRecurrence[{1, 3, -3}, {1, 2, 3, 6, 11}, 61]
PROG
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
G. C. Greubel, Oct 31 2022
STATUS
approved