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A080210
Lower bound for the multiplicity of a disjoint covering system of congruences.
0
1, 2, 3, 2, 5, 2, 7, 2, 3, 3, 11, 2, 13, 4, 3, 2, 17, 2, 19, 3, 5, 6, 23, 2, 5, 7, 3, 4, 29, 2, 31, 2, 7, 9, 5, 2, 37, 10, 9, 3, 41, 3, 43, 6, 3, 12, 47, 2, 7, 3, 11, 7, 53, 2, 9, 4, 13, 15, 59, 2, 61, 16, 5, 2, 10, 4, 67, 9, 15, 3, 71, 2, 73, 19, 3, 10, 9, 5, 79, 3, 3, 21, 83, 3, 13, 22, 19, 6, 89
OFFSET
1,2
FORMULA
a(n) = floor(Lpf(n)*phi(n)/n) + 1 where Lpf(n) is the largest prime factor of n and phi is the Euler totient function.
CROSSREFS
Cf. A080340.
Sequence in context: A134332 A276632 A273288 * A126594 A363895 A086765
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Mar 20 2003
STATUS
approved