OFFSET
0,1
COMMENTS
Previous name was: -1 + Sum of first 10^n + 1 odd numbers.
LINKS
Colin Barker, Table of n, a(n) for n = 0..499
Index entries for linear recurrences with constant coefficients, signature (110,-1000).
FORMULA
a(n) = (10^n+1)^2 - 1. - N. J. A. Sloane, Oct 15 2007
From Colin Barker, Jan 27 2015: (Start)
a(n) = 110*a(n-1) - 1000*a(n-2).
G.f.: -3*(70*x-1)/((10*x-1)*(100*x-1)). (End)
From Elmo R. Oliveira, Nov 21 2025: (Start)
E.g.f.: exp(10*x)*(2 + exp(90*x)).
a(n) = A033934(n) - 1. (End)
MATHEMATICA
LinearRecurrence[{110, -1000}, {3, 120}, 15] (* or *) CoefficientList[Series[-3*(70*x-1) / ((10*x-1)*(100*x-1)), {x, 0, 14}], x] (* James C. McMahon, Apr 05 2025 *)
PROG
(PARI) Vec(-3*(70*x-1)/((10*x-1)*(100*x-1)) + O(x^20)) \\ Colin Barker, Jan 27 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Oct 14 2007
EXTENSIONS
Edited by N. J. A. Sloane, Oct 15 2007
Offset and name corrected by Arkadiusz Wesolowski, Jun 12 2013
New name (using formula by N. J. A. Sloane) from Joerg Arndt, Jan 27 2015
STATUS
approved