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%I #27 Jan 15 2021 06:05:14
%S 0,16,34,54,76,100,126,154,184,216,250,286,324,364,406,450,496,544,
%T 594,646,700,756,814,874,936,1000,1066,1134,1204,1276,1350,1426,1504,
%U 1584,1666,1750,1836,1924,2014,2106,2200,2296,2394,2494
%N a(n) = n*(n+15).
%H Felix P. Muga II, <a href="https://www.researchgate.net/publication/267327689_Extending_the_Golden_Ratio_and_the_Binet-de_Moivre_Formula">Extending the Golden Ratio and the Binet-de Moivre Formula</a>, Preprint on ResearchGate, March 2014.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F a(n) = n*(n + 15).
%F a(n) = 2*A056121(n). - _Reinhard Zumkeller_, Mar 20 2009
%F a(n) = 2*n + a(n-1) + 14 (with a(0)=0). - _Vincenzo Librandi_, Aug 03 2010
%F G.f.: 2*x*(-8+7*x) / (x-1)^3 . - _R. J. Mathar_, Jul 14 2012
%F Sum_{n>=1} 1/a(n) = 1195757/5405400 = 0.22121526621... - _R. J. Mathar_, Jul 14 2012
%F Sum_{n>=1} (-1)^(n+1)/a(n) = 2*log(2)/15 - 52279/1081080. - _Amiram Eldar_, Jan 15 2021
%t s=0;lst={};Do[s+=n;AppendTo[lst,s],{n,16,6!,2}];lst (* _Vladimir Joseph Stephan Orlovsky_, Feb 26 2009 *)
%t Table[n(n+15),{n,0,60}] (* or *) LinearRecurrence[{3,-3,1},{0,16,34},60] (* _Harvey P. Dale_, Jan 20 2019 *)
%o (PARI) a(n)=n*(n+15) \\ _Charles R Greathouse IV_, Sep 24 2015
%Y Cf. A002378, A001477, A056121, A056126, A098849, A120071, A132761, A132765.
%K easy,nonn
%O 0,2
%A _Omar E. Pol_, Aug 28 2007
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