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%I #19 Sep 08 2022 08:45:38
%S 8,27,63,122,210,333,497,708,972,1295,1683,2142,2678,3297,4005,4808,
%T 5712,6723,7847,9090,10458,11957,13593,15372,17300,19383,21627,24038,
%U 26622,29385,32333,35472,38808,42347,46095,50058,54242,58653,63297
%N Row sums of A154685.
%H Vincenzo Librandi, <a href="/A151675/b151675.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 a(n)=n*(2*n^2+5*n+9)/2 = 4*a(n-1)-6*a(n-2)+4*a(n-3)-a(n-4). G.f.: x*(8-5*x+3*x^2)/(x-1)^4. [From _R. J. Mathar_, May 31 2009]
%F a(n) = A162261(n) + 8*n. - _L. Edson Jeffery_, Oct 12 2012
%t CoefficientList[Series[(8-5*x+3*x^2)/(x-1)^4,{x,0,40}],x] (* _Vincenzo Librandi_, Jun 30 2012 *)
%o (Magma) I:=[8, 27, 63, 122]; [n le 4 select I[n] else 4*Self(n-1)-6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..50]]; // _Vincenzo Librandi_, Jun 30 2012
%Y Cf. A162261.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, May 31 2009
%E Extended by _R. J. Mathar_, May 31 2009