A037666 Decimal expansion of a(n) is given by the first n terms of the periodic sequence with initial period 3,1,0.

3, 31, 310, 3103, 31031, 310310, 3103103, 31031031, 310310310, 3103103103, 31031031031, 310310310310, 3103103103103, 31031031031031, 310310310310310, 3103103103103103

Offset

1,1

Links

Table of n, a(n) for n=1..16.

Index entries for linear recurrences with constant coefficients, signature (10,0,1,-10).

Formula

G.f.: x*(3+x) / ( (x-1)*(10*x-1)*(1+x+x^2) ). - R. J. Mathar, Aug 04 2013

Mathematica

Table[FromDigits[PadRight[{}, n, {3, 1, 0}]], {n, 30}] (* or *) LinearRecurrence[ {10, 0, 1, -10}, {3, 31, 310, 3103}, 30] (* Harvey P. Dale, Oct 11 2020 *)

Prog

(PARI) Vec(x*(3+x)/((x-1)*(10*x-1)*(1+x+x^2)) + O(x^25)) \\ Jinyuan Wang, Apr 14 2020

Crossrefs

Sequence in context: A069589 A222090 A037778 * A065837 A100894 A065533

Adjacent sequences: A037663 A037664 A037665 * A037667 A037668 A037669

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved