A173833 - OEIS

%I #17 Jun 17 2017 03:56:13

%S 7,97,997,9997,99997,999997,9999997,99999997,999999997,9999999997,

%T 99999999997,999999999997,9999999999997,99999999999997,

%U 999999999999997,9999999999999997,99999999999999997,999999999999999997

%N 10^n - 3.

%H Vincenzo Librandi, <a href="/A173833/b173833.txt">Table of n, a(n) for n = 1..100</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-10).

%F a(n) = 10*a(n-1)+27 with n>1, a(1)=7.

%F G.f.: x*(20*x+7)/((x-1)*(10*x-1)). [_Colin Barker_, Jan 24 2013]

%t LinearRecurrence[{11, -10}, {7, 97}, 20] (* _Vincenzo Librandi_, Feb 22 2012 *)

%o (PARI) a(n)=10^n-3 \\ _Charles R Greathouse IV_, Jan 11 2012

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Feb 26 2010