login
A033145
Base 9 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,0.
2
1, 9, 81, 730, 6570, 59130, 532171, 4789539, 43105851, 387952660, 3491573940, 31424165460, 282817489141, 2545357402269, 22908216620421, 206173949583790, 1855565546254110, 16700089916286990, 150300809246582911, 1352707283219246199, 12174365548973215791
OFFSET
1,2
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
KEYWORD
nonn,base,easy
EXTENSIONS
More terms from Michel Marcus, Jul 18 2014
STATUS
approved