A134230 - OEIS

%I #15 Jun 13 2015 00:52:32

%S 3,120,10200,1002000,100020000,10000200000,1000002000000,

%T 100000020000000,10000000200000000,1000000002000000000,

%U 100000000020000000000,10000000000200000000000,1000000000002000000000000,100000000000020000000000000,10000000000000200000000000000

%N a(n) = (10^n+1)^2-1.

%C Previous name was: -1 + Sum of first 10^n + 1 odd numbers.

%H Colin Barker, <a href="/A134230/b134230.txt">Table of n, a(n) for n = 0..499</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (110,-1000).

%F a(n) = (10^n+1)^2-1. - _N. J. A. Sloane_, Oct 15 2007

%F a(n) = 110*a(n-1)-1000*a(n-2). - _Colin Barker_, Jan 27 2015

%F G.f.: -3*(70*x-1) / ((10*x-1)*(100*x-1)). - _Colin Barker_, Jan 27 2015

%o (PARI) Vec(-3*(70*x-1)/((10*x-1)*(100*x-1))  + O(x^100)) \\ _Colin Barker_, Jan 27 2015

%Y Cf. A134228, A134229.

%K easy,nonn

%O 0,1

%A _Enoch Haga_, Oct 14 2007

%E Edited by _N. J. A. Sloane_, Oct 15 2007

%E Offset and name corrected by _Arkadiusz Wesolowski_, Jun 12 2013

%E New name (using formula by _N. J. A. Sloane_) from _Joerg Arndt_, Jan 27 2015