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 A328590 #6 Oct 21 2019 19:27:32
%S A328590 0,1,0,2,0,0,0,2,0,3,0,-1,0,3,0,2,0,0,0,4,0,4,0,-1,0,4,0,5,0,-2,0,2,0,
%T A328590 1,0,0,0,3,0,4,0,-1,0,4,0,4,0,0,0,5,0,5,0,-1,0,5,0,3,0,-2,0,3,0,2,0,0,
%U A328590 0,4,0,4,0,-1,0,5,0,5,0,0,0,5,0,6,0,-1,0,4,0,6,0,-2,0,4,0,5,0,0,0,5,0,5,0,-1,0,5,0
%N A328590 a(n) = A328578(n) - A257993(n).
%H A328590 Antti Karttunen, <a href="/A328590/b328590.txt">Table of n, a(n) for n = 1..65537</a>
%H A328590 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F A328590 a(n) = A328578(n) - A257993(n).
%o A328590 (PARI)
%o A328590 A257993(n) = { for(i=1,oo,if(n%prime(i),return(i))); }
%o A328590 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A328590 A328578(n) = A257993(A276086(A276086(n)));
%o A328590 A328590(n) = (A328578(n) - A257993(n));
%Y A328590 Cf. A257993, A276086, A328578, A328585 (positions of zeros), A328587 (of negative terms), A328588 (of positive terms).
%Y A328590 Cf. A328591 (even bisection).
%K A328590 sign
%O A328590 1,4
%A A328590 _Antti Karttunen_, Oct 21 2019