The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A030439 a(n+1) = smallest number not containing any digits of a(n), working in base 3. 1
 0, 1, 2, 3, 8, 9, 26, 27, 80, 81, 242, 243, 728, 729, 2186, 2187, 6560, 6561, 19682, 19683, 59048, 59049, 177146, 177147, 531440, 531441, 1594322, 1594323, 4782968, 4782969, 14348906, 14348907, 43046720, 43046721, 129140162, 129140163, 387420488, 387420489 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA 3^i-1 then 3^i. a(n) = 4*a(n-2)-3*a(n-4); g.f.: -x*(x^2-2*x-1) / ((x-1)*(x+1)*(3*x^2-1)). - Colin Barker, Sep 13 2014 a(n) = 3^floor(n/2) -1 +(n mod 2). - Alois P. Heinz, Sep 14 2014 CROSSREFS Cf. A030283. Bisections give: A024023, A000244. Sequence in context: A163168 A085453 A271394 * A119386 A162219 A140484 Adjacent sequences:  A030436 A030437 A030438 * A030440 A030441 A030442 KEYWORD nonn,base 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 6 01:03 EDT 2021. Contains 343579 sequences. (Running on oeis4.)