OFFSET
0,3
COMMENTS
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
Robert Munafo, Sequences Related to "Floretions".
Index entries for linear recurrences with constant coefficients, signature (1,3,1).
FORMULA
a(n) = (1/4*sqrt(2)-1/4)*(1+sqrt(2))^n + (-1/4*sqrt(2)-1/4)*(1-sqrt(2))^n + 3/2*(-1)^n.
G.f.: (2*x-1)/((x+1)*(x^2+2*x-1)).
a(n) = 3*(-1)^n/2+A001333(n-1)/2, n>0. [R. J. Mathar, Nov 10 2009]
MATHEMATICA
LinearRecurrence[{1, 3, 1}, {1, -1, 2}, 30] (* Harvey P. Dale, Jul 26 2020 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Creighton Dement, Oct 29 2005
STATUS
approved