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%I #6 Oct 30 2019 09:24:14
%S 0,0,0,0,0,3,2,2,3,0,3,4,3,3,3,4,3,5,2,2,3,4,3,4,3,3,3,4,3,4,0,3,3,3,
%T 4,4,2,2,3,0,3,5,3,3,3,5,3,5,2,2,3,5,3,5,3,3,3,5,3,6,3,4,3,3,3,3,2,2,
%U 3,5,3,5,3,3,3,5,3,5,2,2,3,5,3,5,3,3,3,5,3,5,3,3,4,3,3,3,2,2,3,5,3,5,3,3,3,5
%N Index of the least significant digit > 1 in the primorial base expansion of A276086(n), 0 if no such digit exists.
%C a(n) = index of the least non-unitary prime divisor of A276087(n) or 0 if no such prime-divisor exists.
%H Antti Karttunen, <a href="/A328829/b328829.txt">Table of n, a(n) for n = 0..65537</a>
%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F a(n) = A328828(A276086(n)) = A277885(A276087(n)).
%o (PARI)
%o A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A328828(n) = { my(i=1, p=2); while(n, if((n%p)>1, return(i)); i++; n = n\p; p = nextprime(1+p)); (0); };
%o A328829(n) = A328828(A276086(n));
%o (PARI)
%o A277885(n) = if(1==n,0,my(f=factor(n)); for(i=1,#f~,if(f[i,2]>1,return(primepi(f[i,1])))); (0));
%o A328829(n) = A277885(A276086(A276086(n)));
%Y Cf. A276086, A276087, A277885, A328828, A328836 (positions of zeros).
%K nonn
%O 0,6
%A _Antti Karttunen_, Oct 29 2019
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