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 A325668 #14 Feb 20 2022 08:15:13
%S A325668 2,0,0,0,1,-5,15,-35,71,-135,255,-495,991,-2015,4095,-8255,16511,
%T A325668 -32895,65535,-130815,261630,-523753,1048322,-2096151,4183700,
%U A325668 -8324849,16480854,-32363019,62784774,-119759849,223346544,-404491999,705032194,-1166803109
%N A325668 First term of n-th difference sequence of (floor(k*r)), r = sqrt(5), k >= 0.
%H A325668 Clark Kimberling, <a href="/A325668/b325668.txt">Table of n, a(n) for n = 1..200</a>
%t A325668 Table[First[Differences[Table[Floor[Sqrt[5]*n], {n, 0, 50}], n]], {n, 1, 50}]
%Y A325668 Cf. A325664, A325669.
%Y A325668 Inverse binomial transform of A022839.
%K A325668 easy,sign
%O A325668 1,1
%A A325668 _Clark Kimberling_, May 13 2019