A037602 Base 9 digits are, in order, the first n terms of the periodic sequence with initial period 1,3,0.

1, 12, 108, 973, 8760, 78840, 709561, 6386052, 57474468, 517270213, 4655431920, 41898887280, 377089985521, 3393809869692, 30544288827228, 274898599445053, 2474087395005480

Offset

1,2

Links

Table of n, a(n) for n=1..17.

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

Index entries for 3-automatic sequences.

Formula

G.f.: x*(1+3*x) / ( (x-1)*(9*x-1)*(1+x+x^2) ). - R. J. Mathar, Apr 27 2015

A007095(a(n)) = A037603(n). - R. J. Mathar, Apr 27 2015

Mathematica

Table[FromDigits[PadRight[{}, n, {1, 3, 0}], 9], {n, 20}] (* or *) LinearRecurrence[{9, 0, 1, -9}, {1, 12, 108, 973}, 20] (* Harvey P. Dale, Feb 12 2025 *)

Prog

(PARI) a(n)=([0, 1, 0, 0; 0, 0, 1, 0; 0, 0, 0, 1; -9, 1, 0, 9]^(n-1)*[1; 12; 108; 973])[1, 1] \\ Charles R Greathouse IV, Feb 13 2017

Crossrefs

Sequence in context: A111990 A053469 A055533 * A037707 A140317 A069653

Adjacent sequences: A037599 A037600 A037601 * A037603 A037604 A037605

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved