A033145 Base 9 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,0.

1, 9, 81, 730, 6570, 59130, 532171, 4789539, 43105851, 387952660, 3491573940, 31424165460, 282817489141, 2545357402269, 22908216620421, 206173949583790, 1855565546254110, 16700089916286990, 150300809246582911, 1352707283219246199, 12174365548973215791

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (9,0,1,-9)

Formula

a(n) = +9*a(n-1) +a(n-3) -9*a(n-4). G.f.: x / ( (x-1)*(9*x-1)*(1+x+x^2) ). - R. J. Mathar, Jan 08 2011

a(n) = floor((81/728)*9^n). - Tani Akinari, Jul 18 2014

Example

The first six terms have base 9 representations 1, 10, 100, 1001, 10010, 100100.

Mathematica

Table[FromDigits[PadRight[{}, n, {1, 0, 0}], 9], {n, 30}] (* Harvey P. Dale, Dec 18 2018 *)

Prog

(PARI) Vec(x / ( (x-1)*(9*x-1)*(1+x+x^2) )+ O(x^30)) \\ Michel Marcus, Jul 18 2014

Crossrefs

Sequence in context: A158779 A047901 A061587 * A158762 A101601 A233737

Adjacent sequences: A033142 A033143 A033144 * A033146 A033147 A033148

Keyword

nonn,base,easy

Author

Clark Kimberling

Extensions

More terms from Michel Marcus, Jul 18 2014

Status

approved