A179526 (3^k - 1)/2 appears 3^(k-1) times, k>0.

1, 4, 4, 4, 13, 13, 13, 13, 13, 13, 13, 13, 13, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121, 121

Offset: 0

Author

Reinhard Zumkeller, Jul 18 2010

Keywords

• nonn

Crossrefs

Cf. A003462, A007448, A003817.

Programs

Mathematica

Table[PadRight[{},3^(k-1),(3^k-1)/2],{k,5}]//Flatten (* Harvey P. Dale, May 30 2021 *)

Formula

a(n+1) = 3*a(floor(n/3)) + 1; a(0) = 1.

Extensions

Erroneous comment deleted by Reinhard Zumkeller, Jul 23 2010