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 A296911 #10 Aug 30 2023 17:15:20 %S A296911 1,5,11,25,39,61,83,113,143,181,219,265,311,365,419,481,543,613,683, %T A296911 761,839,925,1011,1105,1199,1301,1403,1513,1623,1741,1859,1985,2111, %U A296911 2245,2379,2521,2663,2813,2963,3121,3279,3445,3611,3785,3959,4141,4323,4513,4703,4901,5099,5305,5511,5725 %N A296911 Partial sums of A296910. %H A296911 Robert Israel, <a href="/A296911/b296911.txt">Table of n, a(n) for n = 0..10000</a> %H A296911 Reticular Chemistry Structure Resource (RCSR), <a href="http://rcsr.net/layers/bew">The bew tiling (or net)</a> %H A296911 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2, 0, -2, 1). %F A296911 From _Robert Israel_, Dec 22 2017: (Start) %F A296911 a(n) = 2*n^2 + 2*n - (-1)^n for n >= 1. %F A296911 G.f.: (1+3*x+x^2+5*x^3-2*x^4)/((1+x)*(1-x)^3). (End) %p A296911 1, seq(2*n^2 + 2*n - (-1)^n,n=1..100); # _Robert Israel_, Dec 22 2017 %K A296911 nonn %O A296911 0,2 %A A296911 _N. J. A. Sloane_, Dec 22 2017