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A328591 Even bisection of A328590: a(n) = A328578(2n) - A257993(2n).

%I A328591 #5 Oct 21 2019 19:27:41
%S A328591 1,2,0,2,3,-1,3,2,0,4,4,-1,4,5,-2,2,1,0,3,4,-1,4,4,0,5,5,-1,5,3,-2,3,
%T A328591 2,0,4,4,-1,5,5,0,5,6,-1,4,6,-2,4,5,0,5,5,-1,5,6,0,6,3,-1,7,7,-2,1,5,
%U A328591 0,6,6,-1,6,5,0,7,7,-1,7,8,-2,2,1,0,6,7,-1,7,3,0,7,5,-1,3,8,-2,6,2,0,7,7,-1,7,8,0,8,8,-1,8,9,-1
%N A328591 Even bisection of A328590: a(n) = A328578(2n) - A257993(2n).
%H A328591 Antti Karttunen, <a href="/A328591/b328591.txt">Table of n, a(n) for n = 1..16384</a>
%H A328591 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F A328591 a(n) = A328590(2n) = A328578(2n) - A257993(2n).
%o A328591 (PARI)
%o A328591 A257993(n) = { for(i=1,oo,if(n%prime(i),return(i))); }
%o A328591 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A328591 A328578(n) = A257993(A276086(A276086(n)));
%o A328591 A328590(n) = (A328578(n) - A257993(n));
%o A328591 A328591(n) = A328590(n+n);
%Y A328591 Cf. A257993, A276086, A328578, A328590.
%K A328591 sign
%O A328591 1,2
%A A328591 _Antti Karttunen_, Oct 21 2019