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A329346 a(n) = A322356(A324886(n)).

%I A329346 #6 Nov 11 2019 18:43:53
%S A329346 1,1,1,1,1,1,1,5,7,1,1,1,1,1,1,5,1,7,1,1,1,1,1,7,1,1,1,1,1,1,1,1,1,1,
%T A329346 13,7,1,1,1,1,1,13,1,1,1,1,1,7,13,1,1,1,1,1,1,1,1,1,1,1,1,1,13,1,19,1,
%U A329346 1,1,1,13,1,7,1,1,13,1,1,1,1,1,7,1,1,13,1,1,1,1,1,1,19,1,1,1,1,7,1,13,1,13,1,1,1,1,13
%N A329346 a(n) = A322356(A324886(n)).
%H A329346 Antti Karttunen, <a href="/A329346/b329346.txt">Table of n, a(n) for n = 1..65537</a>
%H A329346 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A329346 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A329346 <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%F A329346 a(n) = A322356(A324886(n)).
%e A329346 For n = 128 = 2^7, A108951(128) = A034386(2)^7 = 128. As 128 = 4 * 30 + 1*6 + 1* 2, A276086(128) = 36015 = 7^4 * 5^1 * 3^1, and there are two such primes that both p and p-2 divide n, and p-2 is also prime, namely, 7 and 5, thus a(128) = 7*5 = 35. This is also the first occurrence of composite number in this sequence.
%o A329346 (PARI)
%o A329346 A034386(n) = prod(i=1, primepi(n), prime(i));
%o A329346 A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };  \\ From A108951
%o A329346 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A329346 A324886(n) = A276086(A108951(n));
%o A329346 A322356(n) = { my(f = factor(n), m=1); for(i=1, #f~, if(isprime(f[i,1]+2)&&!(n%(f[i,1]+2)), m *= (f[i,1]+2))); (m); };
%o A329346 A329346(n) = A322356(A324886(n));
%Y A329346 Cf. A002110, A034386, A108951, A276086, A324886, A329040, A322356, A329343, , A329344, A329347, A329348.
%K A329346 nonn
%O A329346 1,8
%A A329346 _Antti Karttunen_, Nov 11 2019