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%I #18 Sep 08 2022 08:44:49
%S 105,168,246,340,451,580,728,896,1085,1296,1530,1788,2071,2380,2716,
%T 3080,3473,3896,4350,4836,5355,5908,6496,7120,7781,8480,9218,9996,
%U 10815,11676,12580,13528,14521,15560,16646,17780,18963,20196,21480,22816,24205,25648,27146,28700,30311
%N dot_product(n,n-1,...2,1)*(7,8,...,n,1,2,3,4,5,6).
%H Vincenzo Librandi, <a href="/A026066/b026066.txt">Table of n, a(n) for n = 7..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) = (1/6) * (n^2 + 21n - 106) * n. - _Ralf Stephan_, Apr 05 2004
%F G.f.: x^7*(105-252*x+204*x^2-56*x^3)/(1-x)^4. - _Colin Barker_, Sep 17 2012
%t CoefficientList[Series[(105 - 252 x + 204 x^2 - 56 x^3)/(1 - x)^4, {x, 0, 60}], x] (* _Vincenzo Librandi_, Oct 17 2013 *)
%o (Magma) [n*(n^2+21*n-106)/6: n in [7..60]]; // _Vincenzo Librandi_, Oct 17 2013
%Y Column 6 of triangle A094415.
%K nonn,easy
%O 7,1
%A _Clark Kimberling_
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