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 A080063 #5 Sep 01 2025 23:29:14 %S A080063 1,2,3,1,5,0,7,2,1,1,11,0,13,2,3,1,17,0,19,2,1,1,23,0,1,2,3,1,29,0,31, %T A080063 2,1,1,5,0,37,2,3,1,41,0,43,2,1,1,47,0,1,2,3,1,53,0,1,2,1,1,59,0,61,2, %U A080063 3,1,5,0,67,2,1,1,71,0,73,2,3,1,5,0,79,2,1,1,83,0,1,2,3,1,89,0,3,2,1,1,5,0 %N A080063 a(n) = n mod (spf(n)+1), where spf(n) is the smallest prime dividing n (A020639). %C A080063 a(n) = 0 iff n mod 6 = 0 (A008588); %C A080063 a(n) = 2 iff n mod 6 = 2 (A016933); %C A080063 for n>1: a(n)=n iff n is prime (A000040, A008578). %Y A080063 Cf. A080064, A080065, A010872, A010873, A010875, A010877, A010881. %K A080063 nonn,changed %O A080063 1,2 %A A080063 _Reinhard Zumkeller_, Jan 24 2003