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 A004650 #24 Oct 26 2023 08:33:25
%S A004650 0,0,1,2,5,6,1,1,3,7,7,11,13,13,15,2,5,4,7,8,7,10,11,14,19,20,19,20,
%T A004650 19,20,31,32,1,34,5,3,5,7,7,9,11,9,15,13,13,11,19,27,27,25,25,27,25,
%U A004650 31,33,35,37,35,37,37,35,41,51,51,49,49,59,61,67,65,65,67
%N A004650 a(n) = prime(n) mod (n+1).
%H A004650 Vincenzo Librandi, <a href="/A004650/b004650.txt">Table of n, a(n) for n = 1..1000</a>
%t A004650 Table[Mod[Prime[n], n + 1], {n, 1, 90}] (* _Vincenzo Librandi_, Sep 11 2014 *)
%o A004650 (PARI) a(n) = prime(n) % (n+1) \\ _Michel Marcus_, Jun 12 2013
%o A004650 (Magma) [NthPrime(n) mod (n+1): n in [1..90]]; // _Vincenzo Librandi_, Sep 11 2014
%Y A004650 Cf. A004648, A004649.
%K A004650 nonn,easy
%O A004650 1,4
%A A004650 _N. J. A. Sloane_, Daniel Wild (wild(AT)edumath.u-strasbg.fr)