OFFSET
0,2
COMMENTS
LINKS
FORMULA
a(3n)=3*a(n), a(3n+1)=3n+2, a(3n+2)=9n+3
MATHEMATICA
a[n_] := a[n] = Which[ Mod[n, 3] == 0, 3*a[n/3], Mod[n, 3] == 1, n+1, True, 3*(n-1)]; Table[a[n], {n, 0, 65}] (* Jean-François Alcover, Sep 24 2012 *)
PROG
(Haskell)
import Data.List (transpose)
a002517 n = a002517_list !! n
a002517_list = 0 : concat
(transpose [[2, 5 ..], [3, 12 ..], map (* 3) $ tail a002517_list])
-- Reinhard Zumkeller, Jun 04 2015
CROSSREFS
KEYWORD
nonn,nice,easy
AUTHOR
EXTENSIONS
Formula and more terms from Henry Bottomley, Apr 27 2000
STATUS
approved