A037778 Decimal expansion of a(n) is given by the first n terms of the periodic sequence with initial period 3,1,0,2.

3, 31, 310, 3102, 31023, 310231, 3102310, 31023102, 310231023, 3102310231, 31023102310, 310231023102, 3102310231023, 31023102310231, 310231023102310, 3102310231023102, 31023102310231023, 310231023102310231, 3102310231023102310, 31023102310231023102

Offset

1,1

Links

Table of n, a(n) for n=1..20.

Index entries for linear recurrences with constant coefficients, signature (11,-11,11,-10).

Formula

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

Mathematica

nn=20; With[{c=PadRight[{}, nn, {3, 1, 0, 2}]}, Table[FromDigits[Take[c, n]], {n, nn}]] (* Harvey P. Dale, May 26 2012 *)

Prog

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

Crossrefs

Sequence in context: A222094 A069589 A222090 * A037666 A065837 A100894

Adjacent sequences: A037775 A037776 A037777 * A037779 A037780 A037781

Keyword

nonn,base,easy

Author

Clark Kimberling

Extensions

More terms from Harvey P. Dale, May 26 2012

Status

approved