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A351945
a(n) = A342001(A181819(n)).
7
0, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 5, 1, 2, 2, 1, 1, 5, 1, 5, 2, 2, 1, 7, 1, 2, 1, 5, 1, 3, 1, 1, 2, 2, 2, 2, 1, 2, 2, 7, 1, 3, 1, 5, 5, 2, 1, 9, 1, 5, 2, 5, 1, 7, 2, 7, 2, 2, 1, 8, 1, 2, 5, 1, 2, 3, 1, 5, 2, 3, 1, 8, 1, 2, 5, 5, 2, 3, 1, 9, 1, 2, 1, 8, 2, 2, 2, 7, 1, 8, 2, 5, 2, 2, 2, 13, 1, 5, 5, 2, 1, 3, 1, 7, 3
OFFSET
1,6
FORMULA
a(n) = A342001(A181819(n)) = A351942(n) / A351944(n).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A003557(n) = (n/factorback(factorint(n)[, 1]));
A181819(n) = factorback(apply(e->prime(e), (factor(n)[, 2])));
A342001(n) = (A003415(n) / A003557(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 02 2022
STATUS
approved