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A328097
If A327928(n) is zero, a(n) = A003415(n), otherwise a(n) = A327859(n) = A276086(A003415(n)).
6
0, 1, 1, 9, 1, 5, 1, 25, 6, 7, 1, 225, 1, 9, 15, 21, 1, 21, 1, 625, 10, 13, 1, 525, 10, 15, 3750, 21, 1, 31, 1, 18375, 14, 19, 25, 49, 1, 21, 225, 735, 1, 41, 1, 875, 39, 25, 1, 385875, 14, 45, 375, 13125, 1, 36750, 225, 1029, 22, 31, 1, 1029, 1, 33, 51, 2941225, 18, 61, 1, 1225, 26, 59, 1, 84035, 1, 39, 55, 18375, 18, 71, 1, 31513125, 42875
OFFSET
1,4
COMMENTS
After zero, sequence contains only terms of A048103.
Note that there are fixed points, like a(15) = 15.
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A129251(n) = { my(f = factor(n)); sum(k=1, #f~, (f[k, 2]>=f[k, 1])); };
A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };
A328097(n) = if(1==n, 0, my(u=A003415(n)); if(!A129251(u), u, A276086(u)));
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 07 2019
STATUS
approved