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 A055976 #14 Feb 19 2024 10:28:12
%S A055976 0,0,0,3,0,1,0,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,
%T A055976 1,1,0,1,1,1,0,1,0,1,1,1,0,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,0,1,
%U A055976 1,1,0,1,0,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1
%N A055976 Remainder when (n-1)! + 1 is divided by n.
%C A055976 Related to Wilson's theorem. a(n) = 0 iff n = 1 or a prime; a(n) = 1 iff n > 4 is composite; a(n) = 3 iff n = 4.
%D A055976 Albert H. Beiler, Recreations in The Theory of Numbers, The Queen of Mathematics Entertains, Second Edition, Dover Publications, Inc., New York, 1966, Page 50.
%H A055976 Antti Karttunen, <a href="/A055976/b055976.txt">Table of n, a(n) for n = 1..10000</a>
%t A055976 Do[Print[Mod[(n-1)!+1, n]], {n, 1, 100}]
%o A055976 (PARI) A055976(n) = (((n-1)!+1)%n); \\ _Antti Karttunen_, Aug 27 2017
%Y A055976 Cf. A061007.
%K A055976 easy,nonn
%O A055976 1,4
%A A055976 _Robert G. Wilson v_, Jul 23 2000