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 A071782 #7 Feb 18 2023 08:08:59
%S A071782 0,1,1,1,0,2,0,5,3,5,0,2,0,0,0,14,0,6,0,15,7,0,0,18,0,13,18,0,0,0,0,8,
%T A071782 0,17,0,24,0,0,13,15,0,14,0,22,0,0,0,28,0,25,0,39,0,9,0,28,19,29,0,30,
%U A071782 0,0,21,32,0,0,0,17,0,0,0,36,0,37,50,38,0,26,0,10
%N A071782 Sum of distinct squares in Z_n (mod n).
%C A071782 a(n)=0 for prime n>3. - _T. D. Noe_, Sep 06 2005
%H A071782 Antti Karttunen, <a href="/A071782/b071782.txt">Table of n, a(n) for n = 1..16848</a>
%t A071782 a[n_] := Mod[Apply[Plus, Union[Table[Mod[i^2, n], {i, 1, n}]]], n]
%o A071782 (PARI) A071782(n) = (vecsum(Set(vector(n,i,(i^2)%n)))%n); \\ _Antti Karttunen_, Feb 18 2023
%K A071782 nonn
%O A071782 1,6
%A A071782 _Santi Spadaro_, Jun 24 2002