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 A017138 #23 Sep 02 2025 21:57:42
%S A017138 36,196,484,900,1444,2116,2916,3844,4900,6084,7396,8836,10404,12100,
%T A017138 13924,15876,17956,20164,22500,24964,27556,30276,33124,36100,39204,
%U A017138 42436,45796,49284,52900,56644,60516,64516,68644,72900,77284,81796,86436,91204,96100,101124
%N A017138 a(n) = (8*n+6)^2.
%H A017138 Vincenzo Librandi, <a href="/A017138/b017138.txt">Table of n, a(n) for n = 0..10000</a>
%H A017138 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A017138 G.f.: ( -36-88*x-4*x^2 ) / (x-1)^3. - _R. J. Mathar_, Aug 26 2015
%F A017138 From _Amiram Eldar_, Apr 26 2023: (Start)
%F A017138 a(n) = A017137(n)^2.
%F A017138 a(n) = 2^2*A016838(n).
%F A017138 Sum_{n>=0} 1/a(n) = Pi^2/64 - G/8, where G is Catalan's constant (A006752). (End)
%F A017138 E.g.f.: 4*exp(x)*(9 + 40*x + 16*x^2). - _Stefano Spezia_, Sep 02 2025
%t A017138 Table[(8*n + 6)^2, {n, 0, 30}] (* _Amiram Eldar_, Apr 26 2023 *)
%o A017138 (Magma) [(8*n+6)^2: n in [0..35]]; // _Vincenzo Librandi_, Jul 22 2011
%o A017138 (PARI) a(n)=(8*n+6)^2 \\ _Charles R Greathouse IV_, Jun 17 2017
%Y A017138 Cf. A006752, A016838, A017137.
%K A017138 nonn,easy,changed
%O A017138 0,1
%A A017138 _N. J. A. Sloane_