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A098228
a(n) = floor(n/(n-phi(n))) = floor(n/cototient(n)).
0
2, 3, 2, 5, 1, 7, 2, 3, 1, 11, 1, 13, 1, 2, 2, 17, 1, 19, 1, 2, 1, 23, 1, 5, 1, 3, 1, 29, 1, 31, 2, 2, 1, 3, 1, 37, 1, 2, 1, 41, 1, 43, 1, 2, 1, 47, 1, 7, 1, 2, 1, 53, 1, 3, 1, 2, 1, 59, 1, 61, 1, 2, 2, 3, 1, 67, 1, 2, 1, 71, 1, 73, 1, 2, 1, 4, 1, 79, 1, 3, 1, 83, 1, 4, 1, 2, 1, 89, 1, 4, 1, 2, 1, 4, 1, 97
OFFSET
2,1
EXAMPLE
If n=p^j where p is a prime number, then cototient(p^j) = p^j - p^j(p-1/p) = p^(j-1) so n/cototient(n)=p holds for all prime powers.
MATHEMATICA
Table[Floor[n/(n-EulerPhi[n])], {n, 2, 1000}]
CROSSREFS
Sequence in context: A178380 A178375 A086847 * A081303 A369044 A164880
KEYWORD
nonn
AUTHOR
Labos Elemer, Oct 25 2004
STATUS
approved