This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A123143 a(0)=0, a(1)=1, a(2)=2; a(3n)=a(n), a(3n+1)=a(n)+a(n+1), a(3n+2)=a(n+1)+a(n+2) 0
 0, 1, 2, 1, 3, 3, 2, 3, 4, 1, 4, 6, 3, 6, 5, 3, 5, 5, 2, 5, 7, 3, 7, 5, 4, 5, 5, 1, 5, 10, 4, 10, 9, 6, 9, 9, 3, 9, 11, 6, 11, 8, 5, 8, 8, 3, 8, 10, 5, 10, 7, 5, 7, 7, 2, 7, 12, 5, 12, 10, 7, 10, 10, 3, 10, 12, 7, 12, 9, 5, 9, 9, 4, 9, 10, 5, 10, 6, 5, 6, 6, 1, 6, 15, 5, 15, 14, 10, 14, 14, 4, 14, 19 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Similar to A002487 but the base is 3. First occurrence of k beginning with 0: 0,1,2,4,8,14,11,20,41,32,29,38,56,122,86,83,128,113,101,92,110,200,173,347,257,419,..., . - Robert G. Wilson v LINKS EXAMPLE a(11) = a(4)+a(5) = a(1)+a(2)+a(2)+a(3) = 2(a(1)+a(2)) = 6. MAPLE a[0]:=0: a[1]:=1: a[2]:=2: for n from 1 to 38 do a[3*n]:=a[n]: a[3*n+1]:=a[n]+a[n+1]: a[3*n+2]:=a[n+1]+a[n+2] od: seq(a[n], n=0..115); # Emeric Deutsch MATHEMATICA a[0] = 0; a[1] = 1; a[2] = 2; a[n_] := Switch[Mod[n, 3], 0, a[n/3], 1, a[(n - 1)/3] + a[(n + 2)/3], 2, a[(n + 1)/3] + a[(n + 4)/3]]; Table[ a[n], {n, 0, 93}] (* Robert G. Wilson v *) CROSSREFS Sequence in context: A234200 A102746 A287618 * A128133 A032434 A002347 Adjacent sequences:  A123140 A123141 A123142 * A123144 A123145 A123146 KEYWORD nonn AUTHOR WAGNER Kurt (wagner.kurt(AT)chello.at), Oct 01 2006 EXTENSIONS More terms from Robert G. Wilson v and Emeric Deutsch Oct 07 2006 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 19 03:54 EDT 2019. Contains 328211 sequences. (Running on oeis4.)