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%I #31 Sep 08 2022 08:45:55
%S 0,5,23,54,98,155,225,308,404,513,635,770,918,1079,1253,1440,1640,
%T 1853,2079,2318,2570,2835,3113,3404,3708,4025,4355,4698,5054,5423,
%U 5805,6200,6608,7029,7463,7910,8370,8843,9329,9828,10340,10865,11403
%N a(n) = n*(13*n-3)/2.
%H Vincenzo Librandi, <a href="/A186030/b186030.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F G.f.: x*(5+8*x)/(1-x)^3.
%F From _Bruno Berselli_, Sep 05 2011: (Start)
%F a(n) - a(-n) = -A008585(n).
%F a(n) + a(-n) = A152742(n). (End)
%F E.g.f.: (1/2)*(13*x^2 + 10*x)*exp(x). - _G. C. Greubel_, Jul 17 2017
%t Table[n (13n-3)/2,{n,0,60}] (* _Harvey P. Dale_, Feb 24 2011 *)
%o (Magma) [ n*(13*n-3)/2 : n in [0..42] ];
%o (PARI) a(n)=n*(13*n-3)/2 \\ _Charles R Greathouse IV_, Oct 07 2015
%Y Cf. numbers of the form n*(d*n+10-d)/2 indexed in A140090.
%Y Cf. A154609 (first differences).
%Y Cf. A008585, A152742.
%K nonn,easy
%O 0,2
%A _Bruno Berselli_, Feb 11 2011
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