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a(n) = Product_{d|n, d<n} A019565(A291759(d)).
4

%I #7 Jan 29 2022 20:15:57

%S 1,1,1,2,1,2,1,4,1,2,1,24,1,6,1,8,1,12,1,8,3,6,1,480,1,2,1,72,1,120,1,

%T 16,3,2,3,480,1,2,1,32,1,216,1,120,5,6,1,13440,3,60,1,120,1,168,3,

%U 1440,1,6,1,144000,1,10,3,32,1,1080,1,8,3,72,1,26880,1,10,75,24,9,1080,1,128,7,10,1,86400,1,30,3

%N a(n) = Product_{d|n, d<n} A019565(A291759(d)).

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%o (PARI)

%o A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };

%o A048673(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); (1+factorback(f))/2; };

%o A289814(n) = { my(d=digits(n, 3)); fromdigits(vector(#d, i, if (d[i]==2, 1, 0)), 2); } \\ From A289814

%o A291759(n) = A289814(A048673(n));

%o A351032(n) = { my(m=1); fordiv(n,d,if(d<n,m *= A019565(A291759(d)))); (m); };

%Y Cf. A019565, A048673, A289814, A291759, A351030, A351031, A351034 (rgs-transform).

%Y Cf. also A293222.

%K nonn

%O 1,4

%A _Antti Karttunen_, Jan 29 2022