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%I #27 Aug 11 2021 12:07:37
%S 1,14,137,1162,9165,69342,511393,3709874,26619989,189594790,
%T 1343438889,9485451066,66805055773,469669890158,3297861746225,
%U 23135894831938,162205576930917,1136710604184246,7963332057891001
%N Expansion of 1/((1-2x)(1-5x)(1-7x)).
%H Michael De Vlieger, <a href="/A016296/b016296.txt">Table of n, a(n) for n = 0..1182</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (14,-59,70).
%F a(n-2) = ((7^n - 2^n)/5 - (5^n - 2^n)/3)/2. - _Zerinvary Lajos_, Jun 05 2009
%F a(n) = 14*a(n-1) - 59*a(n-2) + 70*a(n-3), n >= 3. - _Vincenzo Librandi_, Mar 16 2011
%F a(n) = 12*a(n-1) - 35*a(n-2) + 2^n, n >= 2. - _Vincenzo Librandi_, Mar 16 2011
%t CoefficientList[Series[1/((1 - 2 x) (1 - 5 x) (1 - 7 x)), {x, 0, 18}], x] (* _Michael De Vlieger_, Jan 31 2018 *)
%t LinearRecurrence[{14,-59,70},{1,14,137},30] (* _Harvey P. Dale_, Aug 11 2021 *)
%o (Sage) [((7^n - 2^n)/5-(5^n - 2^n)/3)/2 for n in range(2,21)] # _Zerinvary Lajos_, Jun 05 2009
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_