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dot_product(n,n-1,...2,1)*(6,7,...,n,1,2,3,4,5).
4

%I #21 Sep 08 2022 08:44:49

%S 71,119,180,255,345,451,574,715,875,1055,1256,1479,1725,1995,2290,

%T 2611,2959,3335,3740,4175,4641,5139,5670,6235,6835,7471,8144,8855,

%U 9605,10395,11226,12099,13015,13975,14980,16031,17129,18275,19470,20715,22011,23359,24760,26215,27725,29291

%N dot_product(n,n-1,...2,1)*(6,7,...,n,1,2,3,4,5).

%H Vincenzo Librandi, <a href="/A026063/b026063.txt">Table of n, a(n) for n = 6..1000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).

%F a(n) = n(n^2+18n-73)/6. - _Ralf Stephan_, Apr 30 2004

%F G.f.: x^6*(71-165*x+130*x^2-35*x^3)/(1-x)^4. - _Colin Barker_, Sep 17 2012

%t CoefficientList[Series[(71 - 165 x + 130 x^2 - 35 x^3)/(1 - x)^4, {x, 0, 60}], x] (* _Vincenzo Librandi_, Oct 17 2013 *)

%o (Magma) [n*(n^2+18*n-73)/6: n in [6..60]]; // _Vincenzo Librandi_, Oct 17 2017

%Y Column 5 of triangle A094415.

%K nonn,easy

%O 6,1

%A _Clark Kimberling_