%I #25 Mar 31 2023 06:08:29
%S 4,19,51,106,190,309,469,676,936,1255,1639,2094,2626,3241,3945,4744,
%T 5644,6651,7771,9010,10374,11869,13501,15276,17200,19279,21519,23926,
%U 26506,29265,32209,35344,38676,42211,45955,49914,54094,58501,63141
%N n*(2*n^2 + 5*n + 1)/2.
%C Row sums from A083487.
%C Row 2 of the convolution array A213831. - _Clark Kimberling_, Jul 04 2012
%H Vincenzo Librandi, <a href="/A162254/b162254.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 From _Vincenzo Librandi_, Mar 04 2012: (Start)
%F G.f.: x*(4 + 3*x - 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 LinearRecurrence[{4,-6,4,-1}, {4, 19, 51, 106}, 50] (* or *) CoefficientList[Series[(4+3*x-x^2)/(1-x)^4,{x,0,40}],x] (* _Vincenzo Librandi_, Mar 04 2012 *)
%o (PARI) a(n)=n*(5*n+1)/2+n^3 \\ _Charles R Greathouse IV_, Jan 11 2012
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jun 29 2009
%E New name from _Charles R Greathouse IV_, Jan 11 2012
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