This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A132762 #39 Mar 14 2022 02:44:58
%S A132762 0,20,42,66,92,120,150,182,216,252,290,330,372,416,462,510,560,612,
%T A132762 666,722,780,840,902,966,1032,1100,1170,1242,1316,1392,1470,1550,1632,
%U A132762 1716,1802,1890,1980,2072,2166,2262,2360,2460,2562,2666,2772,2880,2990,3102,3216
%N A132762 a(n) = n*(n + 19).
%H A132762 G. C. Greubel, <a href="/A132762/b132762.txt">Table of n, a(n) for n = 0..5000</a>
%H A132762 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 A132762 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A132762 a(n) = 2*n + a(n-1) + 18 for n > 0, a(0) = 0. - _Vincenzo Librandi_, Aug 03 2010
%F A132762 From _Chai Wah Wu_, Dec 17 2016: (Start)
%F A132762 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n > 2.
%F A132762 G.f.: 2*x*(10 - 9*x)/(1-x)^3. (End)
%F A132762 a(n) = 2*A051942(n+9). - _R. J. Mathar_, Sep 05 2018
%F A132762 From _Amiram Eldar_, Jan 16 2021: (Start)
%F A132762 Sum_{n>=1} 1/a(n) = H(19)/19 = A001008(19)/A102928(19) = 275295799/1474352880, where H(k) is the k-th harmonic number.
%F A132762 Sum_{n>=1} (-1)^(n+1)/a(n) = 2*log(2)/19 - 33464927/884611728. (End)
%F A132762 E.g.f.: x*(20 + x)*exp(x). - _G. C. Greubel_, Mar 14 2022
%t A132762 Table[n (n + 19), {n, 0, 50}] (* _Bruno Berselli_, Sep 05 2018 *)
%t A132762 LinearRecurrence[{3,-3,1},{0,20,42},60] (* _Harvey P. Dale_, Jun 03 2021 *)
%o A132762 (PARI) a(n)=n*(n+19) \\ _Charles R Greathouse IV_, Jun 17 2017
%o A132762 (Sage) [n*(n+19) for n in (0..50)] # _G. C. Greubel_, Mar 14 2022
%Y A132762 Cf. A001008, A002378, A005563, A028347, A028552, A028557, A028560, A028563, A028566, A028569, A051942, A098603, A098847, A098848, A098849, A098850, A102928, A120071, A132759, A132760, A132761, A132763, A132764, A132765, A132766, A132767.
%K A132762 nonn,easy
%O A132762 0,2
%A A132762 _Omar E. Pol_, Aug 28 2007