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%I #10 Jun 17 2017 03:56:13
%S 40,490,4990,49990,499990,4999990,49999990,499999990,4999999990,
%T 49999999990,499999999990,4999999999990,49999999999990,
%U 499999999999990,4999999999999990,49999999999999990,499999999999999990
%N 5*(10^n-2).
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-10).
%F G.f. 10*x*(4+5*x) / ( (10*x-1)*(x-1) ). - R. J. Mathar, Jan 06 2011
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_