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%I #50 Sep 08 2022 08:44:41
%S 1,23,377,5395,71841,915243,11317657,136994195,1631936081,19201296763,
%T 223714264137,2585856904995,29694425953921,339138685491083,
%U 3855525540397817,43660780944367795,492768590388029361
%N Expansion of 1/((1-2x)(1-10x)(1-11x)).
%H Vincenzo Librandi, <a href="/A016325/b016325.txt">Table of n, a(n) for n = 0..900</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (23,-152,220)
%F From _Zerinvary Lajos_, Jun 05 2009 [corrected by _R. J. Mathar_, Mar 14 2011]: (Start)
%F a(n) = 11^(n+2)/9 + 2^(n-1)/9 - 25*10^n/2.
%F a(n) = A016135(n+1) - A016134(n+1). (End)
%F a(n) = 21*a(n-1) - 110*a(n-2) + 2^n. - _Vincenzo Librandi_, Oct 09 2011
%t CoefficientList[Series[1/((1 - 2 x) (1 - 10 x) (1 - 11 x)), {x, 0, 16}], x] (* _Michael De Vlieger_, Jan 31 2018 *)
%o (Sage) [(11^n - 2^n)/9-(10^n - 2^n)/8 for n in range(2,19)] # _Zerinvary Lajos_, Jun 05 2009
%o (Magma) [(2*11^(n+2) +2^n-225*10^n)/18 : n in [0..20]]; // _Vincenzo Librandi_, Oct 09 2011
%o (PARI) Vec(1/((1-2*x)*(1-10*x)*(1-11*x))+O(x^99)) \\ _Charles R Greathouse IV_, Sep 23 2012
%Y Cf. A016134, A016135.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_
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