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 A325729 #8 May 22 2019 10:19:37
%S A325729 0,1,-1,0,3,-9,18,-27,27,1,-92,309,-771,1716,-3627,7449,-14897,28764,
%T A325729 -52921,91239,-143718,196197,-196197,0,737817,-2785484,7758154,
%U A325729 -18894735,42409968,-89718894,180879813,-349599492,650139687,-1166803109,2028578278
%N A325729 First term of n-th difference sequence of (floor(k*r)), r = sqrt(1/2), k >= 0.
%H A325729 Clark Kimberling, <a href="/A325729/b325729.txt">Table of n, a(n) for n = 1..200</a>
%t A325729 Table[First[Differences[Table[Floor[Sqrt[1/2]*n], {n, 0, 50}], n]], {n, 1, 50}]
%Y A325729 Cf. A325664.
%K A325729 easy,sign
%O A325729 1,5
%A A325729 _Clark Kimberling_, May 19 2019