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Expansion of 1/((1-x)(1-4x)(1-7x)(1-11x)).
2

%I #21 Apr 02 2022 15:54:01

%S 1,23,358,4758,58419,686541,7864936,88727036,991573957,11016698979,

%T 121950785034,1346833901634,14852822151415,163644677778137,

%U 1801937252261452,19834231783445352,218267009404507593

%N Expansion of 1/((1-x)(1-4x)(1-7x)(1-11x)).

%H Vincenzo Librandi, <a href="/A021884/b021884.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (23,-171,457,-308).

%F a(n) = (9*11^(n+3)-35*7^(n+3)+40*4^(n+3)-14)/2520. - _Yahia Kahloune_, May 24 2013

%F a(n) = 23*a(n-1) - 171*a(n-2) + 457*a(n-3) - 308*a(n-4) for n > 3. - _Chai Wah Wu_, Feb 03 2021

%t CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 7 x) (1 - 11 x)), {x, 0, 20}], x] (* _Vincenzo Librandi_, Jul 11 2013 *)

%t LinearRecurrence[{23,-171,457,-308},{1,23,358,4758},20] (* _Harvey P. Dale_, Apr 02 2022 *)

%Y Cf. A019623 (first differences).

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_.