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A037694
Decimal expansion of a(n) is given by the first n terms of the periodic sequence with initial period 1,2,0,3.
0
1, 12, 120, 1203, 12031, 120312, 1203120, 12031203, 120312031, 1203120312, 12031203120, 120312031203, 1203120312031, 12031203120312, 120312031203120, 1203120312031203, 12031203120312031, 120312031203120312, 1203120312031203120, 12031203120312031203
OFFSET
1,2
FORMULA
G.f.: x*(1+2*x+3*x^3) / ( (x-1)*(10*x-1)*(1+x)*(x^2+1) ). - R. J. Mathar, Aug 12 2013
MATHEMATICA
Table[FromDigits[PadRight[{}, n, {1, 2, 0, 3}]], {n, 30}] (* Harvey P. Dale, Oct 18 2016 *)
PROG
(PARI) Vec(x*(1+2*x+3*x^3)/((x-1)*(10*x-1)*(1+x)*(x^2+1)) + O(x^25)) \\ Jinyuan Wang, Apr 14 2020
CROSSREFS
Sequence in context: A004291 A001754 A037511 * A242810 A067102 A361573
KEYWORD
nonn,base,easy
EXTENSIONS
More terms from Harvey P. Dale, Oct 18 2016
STATUS
approved