login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A033130 Base-3 digits are, in order, the first n terms of the periodic sequence with initial period 1,1,0. 1
1, 4, 12, 37, 112, 336, 1009, 3028, 9084, 27253, 81760, 245280, 735841, 2207524, 6622572, 19867717, 59603152, 178809456, 536428369, 1609285108, 4827855324, 14483565973, 43450697920, 130352093760, 391056281281, 1173168843844, 3519506531532, 10558519594597 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = 3*a(n-1) + a(n-3) - 3*a(n-4).
G.f.: x*(1+x) / ((1-x)*(1-3*x)*(1+x+x^2)). - Colin Barker, Dec 24 2015
MATHEMATICA
Module[{nn=30, c}, c=PadRight[{}, nn, {1, 1, 0}]; Table[FromDigits[Take[c, n], 3], {n, nn}]] (* or *) LinearRecurrence[{3, 0, 1, -3}, {1, 4, 12, 37}, 30] (* Harvey P. Dale, Sep 01 2015 *)
PROG
(PARI) Vec(x*(1+x)/((1-x)*(1-3*x)*(1+x+x^2)) + O(x^30)) \\ Colin Barker, Dec 24 2015
CROSSREFS
Sequence in context: A349053 A279277 A101555 * A196918 A099098 A019481
KEYWORD
nonn,base,easy
AUTHOR
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 20 22:01 EDT 2024. Contains 373532 sequences. (Running on oeis4.)