%I #16 Apr 20 2024 10:48:46
%S 1,111,11011,1100011,110000011,11000000011,1100000000011,
%T 110000000000011,11000000000000011,1100000000000000011,
%U 110000000000000000011,11000000000000000000011
%N Bisection of A138144.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (101,-100).
%F From _Colin Barker_, Sep 16 2013: (Start)
%F a(n) = 11+11*10^(2*n-3) for n>2.
%F a(n) = 101*a(n-1)-100*a(n-2) for n>4.
%F G.f.: -x*(10*x-1)*(10*x+1)^2 / ((x-1)*(100*x-1)). (End)
%e n ...... a(n)
%e 1 ....... 1
%e 2 ...... 111
%e 3 ..... 11011
%e 4 .... 1100011
%e 5 ... 110000011
%t LinearRecurrence[{101,-100},{1,111,11011,1100011},20] (* _Harvey P. Dale_, Nov 26 2019 *)
%o (PARI) Vec(-x*(10*x-1)*(10*x+1)^2/((x-1)*(100*x-1)) + O(x^100)) \\ _Colin Barker_, Sep 16 2013
%Y Cf. A135577, A138120, A138146, A152756, A152758, A058764.
%K easy,nonn,base
%O 1,2
%A _Omar E. Pol_, Dec 14 2008
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