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 A165476 #9 Jan 13 2023 10:15:35
%S A165476 0,1,1,-1,1,1,-1,1,1,1,1,1,-1,-1,1,-1,1,1,1,-1,1,-1,1,1,-1,1,-1,-1,1,
%T A165476 1,-1,1,1,-1,1,1,1,-1,-1,1,1,-1,-1,1,1,1,1,1,-1,1,1,-1,-1,-1,-1,1,1,1,
%U A165476 1,1,-1,-1,1,1,1,-1,-1,-1,1,-1,1,-1,1,1,-1,-1,-1,1,1,-1,1,1,-1,1,-1,1
%N A165476 Legendre symbol (n,131071).
%C A165476 131071 is the 6th Mersenne prime, A000668(6).
%C A165476 See row 12251 in triangle A226520, A000040(12251) = 131071. - _Reinhard Zumkeller_, Feb 02 2014
%H A165476 A. Karttunen, <a href="/A165476/b165476.txt">Table of n, a(n) for n = 0..131071</a>
%H A165476 Wikipedia, <a href="http://en.wikipedia.org/wiki/Legendre_symbol">Legendre symbol</a>.
%t A165476 a[n_] := JacobiSymbol[n, 2^17 - 1];
%t A165476 Table[a[n], {n, 0, 100}] (* _Jean-François Alcover_, Jan 13 2023 *)
%o A165476 (Haskell)
%o A165476 a165476 = flip legendreSymbol 131071
%o A165476 -- Where the function legendreSymbol is defined in A097343.
%o A165476 -- _Reinhard Zumkeller_, Feb 02 2014
%Y A165476 Partial sums: A165477.
%Y A165476 Cf. A097343.
%K A165476 sign,mult
%O A165476 0,1
%A A165476 _Antti Karttunen_, Sep 21 2009