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 A328317 #27 Jul 20 2020 02:34:26
%S A328317 1,2,3,2,5,2,5,2,5,2,5,2,5,2
%N A328317 Smallest prime not dividing A328316(n), with a(0) = 1 by convention; Equally, for n > 0, smallest prime dividing A328316(1+n).
%C A328317 a(2n+1) = 2 for all n >= 0. Does the pattern of 5's in the even bisection also continue?
%F A328317 a(0) = 1; and for n > 0, a(n) = A053669(A328316(n)).
%F A328317 a(n) = A020639(A328316(1+n)).
%F A328317 For n >= 1, a(n) = A326810(A328316(n-1)). - _Antti Karttunen_, Nov 15 2019
%o A328317 (PARI)
%o A328317 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A328317 A328316(n) = if(!n,0,A276086(A328316(n-1)));
%o A328317 A053669(n) = forprime(p=2, , if(n%p, return(p))); \\ From A053669
%o A328317 A328317(n) = if(0==n,1,A053669(A328316(n)));
%o A328317 \\ Or alternatively as:
%o A328317 A020639(n)=if(n>1, if(n>n=factor(n, 0)[1, 1], n, factor(n)[1, 1]), 1)
%o A328317 A328317(n) = A020639(A328316(1+n));
%Y A328317 Cf. A020639, A053669, A276086, A326810, A328316, A328318, A328319, A328322, A328323, A328585, A328586, A328633.
%K A328317 nonn,hard,more
%O A328317 0,2
%A A328317 _Antti Karttunen_, Oct 14 2019
%E A328317 a(12)-a(13) from _Jinyuan Wang_, Jul 20 2020