OFFSET
1,2
COMMENTS
Numbers m such that Lucas(m) mod 3 = 2. - Bruno Berselli, Oct 19 2017
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (1,0,1,-1).
FORMULA
G.f.: x^2*(5+2*x+x^2)/((1-x)^2*(1+x+x^2)). - Colin Barker, May 14 2012
a(n) = a(n-1) + a(n-3) - a(n-4) for n>4. - Vincenzo Librandi, May 16 2012
From Wesley Ivan Hurt, Jun 10 2016: (Start)
a(n) = (24*n - 12 + 3*cos(2*n*Pi/3) - 7*sqrt(3)*sin(2*n*Pi/3))/9.
a(3*k) = 8*k-1, a(3*k-1) = 8*k-3, a(3*k-2) = 8*k-8. (End)
MAPLE
A047477:=n->(24*n-12+3*cos(2*n*Pi/3)-7*sqrt(3)*sin(2*n*Pi/3))/9: seq(A047477(n), n=1..100); # Wesley Ivan Hurt, Jun 10 2016
MATHEMATICA
Select[Range[0, 300], MemberQ[{0, 5, 7}, Mod[#, 8]] &] (* Vincenzo Librandi, May 16 2012 *)
PROG
(Magma) I:=[0, 5, 7, 8]; [n le 4 select I[n] else Self(n-1)+Self(n-3)-Self(n-4): n in [1..70]]; // Vincenzo Librandi, May 16 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved