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 A366418 #20 Nov 12 2023 21:46:09
%S A366418 1,2,3,3,5,6,7,3,5,10,11,9,13,14,15,3,17,6,19,9,15,22,23,9,13,26,5,21,
%T A366418 29,30,31,3,33,34,35,9,37,38,39,9,41,18,43,33,25,46,47,9,19,10,51,30,
%U A366418 53,6,25,21,57,58,59,27,61,62,25,3,65,66,67,39,69,70,71,9,73,74,39
%N A366418 Number of distinct integers of the form (x^n + y^n) mod n.
%C A366418 a(p) = p when p is prime. It appears that a(n) stabilizes for the subsequences n = k^m for each fixed k > 1 at large enough m.
%C A366418 a(n) = n if there are more than n/2 distinct integers x^n mod n. - _David A. Corneth_, Oct 16 2023
%H A366418 David A. Corneth, <a href="/A366418/a366418.gp.txt">PARI program</a>
%o A366418 (PARI) { a(n) = my(S,t); S=Set(); for(x=0, n-1, for(y=x, n-1, t=lift(Mod(x,n)^n+Mod(y,n)^n); S=setunion(S,[t]); ); ); #S }
%o A366418 (PARI) a(n) = #setbinop((x,y)->Mod(x,n)^n+Mod(y,n)^n, [0..n-1]); \\ _Michel Marcus_, Oct 12 2023
%o A366418 (PARI) See PARI link \\ _David A. Corneth_, Oct 16 2023
%Y A366418 Cf. A121278, A366419, A195637.
%K A366418 nonn
%O A366418 1,2
%A A366418 _Albert Mukovskiy_, Oct 11 2023