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A319694 Product of A078899(x) for all x encountered when map x -> A252463(x) is iterated, starting from x = A252463(n); a(1) = 1.

%I A319694 #9 Nov 21 2018 20:31:42
%S A319694 1,1,1,1,1,1,1,2,2,1,1,2,1,1,2,6,1,6,1,2,2,1,1,8,6,1,6,2,1,6,1,24,2,1,
%T A319694 6,30,1,1,2,8,1,6,1,2,8,1,1,48,30,30,2,2,1,42,6,8,2,1,1,36,1,1,8,120,
%U A319694 6,6,1,2,2,30,1,240,1,1,30,2,30,6,1,56,24,1,1,36,6,1,2,8,1,64,30,2,2,1,6,432,1,210,8,270,1,6,1,8,36
%N A319694 Product of A078899(x) for all x encountered when map x -> A252463(x) is iterated, starting from x = A252463(n); a(1) = 1.
%H A319694 Antti Karttunen, <a href="/A319694/b319694.txt">Table of n, a(n) for n = 1..16384</a>
%H A319694 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%o A319694 (PARI)
%o A319694 up_to = 16384;
%o A319694 ordinal_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), pt); for(i=1, length(invec), if(mapisdefined(om,invec[i]), pt = mapget(om, invec[i]), pt = 0); outvec[i] = (1+pt); mapput(om,invec[i],(1+pt))); outvec; };
%o A319694 A006530(n) = if(n>1, vecmax(factor(n)[, 1]), 1);
%o A319694 v078899 = ordinal_transform(vector(up_to,n,A006530(n)));
%o A319694 A078899(n) = v078899[n];
%o A319694 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A319694 A252463(n) = if(!(n%2),n/2,A064989(n));
%o A319694 A319694(n) = { my(m=1); while(1<(n=A252463(n)), m *= A078899(n)); (m); };
%Y A319694 Cf. A005940, A078899, A252463.
%Y A319694 Cf. also A319689.
%K A319694 nonn
%O A319694 1,8
%A A319694 _Antti Karttunen_, Nov 21 2018