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%I #22 Jul 05 2020 12:37:15
%S 2,11,30,62,110,177,266,380,522,695,902,1146,1430,1757,2130,2552,3026,
%T 3555,4142,4790,5502,6281,7130,8052,9050,10127,11286,12530,13862,
%U 15285,16802,18416,20130,21947,23870,25902,28046,30305,32682,35180,37802
%N a(n) = (n^3 + 4*n^2 - n)/2.
%C Row 2 of the convolution array A213771. - _Clark Kimberling_, Jul 04 2012
%H Vincenzo Librandi, <a href="/A162260/b162260.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F Row sums from A154614: a(n) = Sum_{m=1..n} (m*n + m + n - 1).
%F From _Vincenzo Librandi_, Mar 05 2012: (Start)
%F G.f.: x*(2 + 3*x - 2*x^2)/(1-x)^4.
%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)
%t CoefficientList[Series[(2+3*x-2*x^2)/(1-x)^4,{x,0,40}],x] (* or *) LinearRecurrence[{4, -6, 4, -1}, {2, 11, 30, 62}, 50] (* _Vincenzo Librandi_, Mar 05 2012 *)
%t Table[(n^3+4 n^2-n)/2,{n,50}] (* _Harvey P. Dale_, Jul 05 2020 *)
%Y Cf. A154614.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jun 29 2009
%E New name from _Vincenzo Librandi_, Mar 05 2012
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