A177097 a(n) = 6*(10^n-5).

30, 570, 5970, 59970, 599970, 5999970, 59999970, 599999970, 5999999970, 59999999970, 599999999970, 5999999999970, 59999999999970, 599999999999970, 5999999999999970, 59999999999999970, 599999999999999970

Offset

1,1

Comments

Apparently 30 times the entries of A067272. - R. J. Mathar, Aug 24 2011

Links

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

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

Formula

G.f.: 30*x*(1+8*x) / ( (10*x-1)*(x-1) ). - R. J. Mathar, Aug 24 2011

a(1)=30, a(2)=570, a(n)=11*a(n-1)-10*a(n-2). [Harvey P. Dale, Oct 10 2011]

Mathematica

Join[{30, 570}, FromDigits/@(Join[{5}, #, {7, 0}]&/@Table[PadLeft[{}, n, 9], {n, 20}])] (* or *) LinearRecurrence[{11, -10}, {30, 570}, 20] (* Harvey P. Dale, Oct 10 2011 *)

Crossrefs

Cf. A067272.

Sequence in context: A285168 A028200 A028181 * A028174 A028149 A028172

Adjacent sequences: A177094 A177095 A177096 * A177098 A177099 A177100

Keyword

nonn,easy

Author

Vincenzo Librandi

Status

approved