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 A186683 #21 Feb 16 2025 08:33:14
%S A186683 0,2,17,5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T A186683 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U A186683 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A186683 Total number of n-digit numbers requiring 18 positive biquadrates in their representation as sum of biquadrates.
%C A186683 A161905(n) + A186650(n) + A186652(n) + A186654(n) + A186656(n) + A186658(n) + A186660(n) + A186662(n) + A186664(n) + A186666(n) + A186668(n) + A186670(n) + A186672(n) + A186674(n) + A186676(n) + A186678(n) + A186681(n) + a(n) + A186685(n) = A052268(n)
%C A186683 a(n) = 0 for n >= 5. - _Nathaniel Johnston_, May 09 2011
%H A186683 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/WaringsProblem.html">Waring's Problem.</a>
%H A186683 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F A186683 a(n) = A186682(n) - A186682(n-1).
%t A186683 PadRight[{0, 2, 17, 5}, 100] (* _Paolo Xausa_, Jul 30 2024 *)
%Y A186683 Cf. A046049, A099591.
%K A186683 nonn,base,easy
%O A186683 1,2
%A A186683 _Martin Renner_, Feb 25 2011