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A327404
Quotient of n over the maximum divisor of n that is 2 or whose prime indices have a common divisor > 1.
0
1, 1, 1, 2, 1, 2, 1, 4, 1, 2, 1, 4, 1, 2, 3, 8, 1, 2, 1, 4, 1, 2, 1, 8, 1, 2, 1, 4, 1, 6, 1, 16, 3, 2, 5, 4, 1, 2, 1, 8, 1, 2, 1, 4, 5, 2, 1, 16, 1, 2, 3, 4, 1, 2, 5, 8, 1, 2, 1, 12, 1, 2, 1, 32, 1, 6, 1, 4, 3, 10, 1, 8, 1, 2, 3, 4, 7, 2, 1, 16, 1, 2, 1, 4, 5
OFFSET
1,4
COMMENTS
First differs from A327395 at a(195) = 65, A327395(195) = 195.
A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
EXAMPLE
The divisors of 90 that are 2 or whose prime indices have a common divisor > 1 are {1, 2, 3, 5, 9}, so a(90) = 90/9 = 10.
MATHEMATICA
Table[n/Max[Select[Divisors[n], #==2||GCD@@PrimePi/@First/@FactorInteger[#]!=1&]], {n, 100}]
CROSSREFS
See link for additional cross-references.
Sequence in context: A230849 A135517 A327395 * A360112 A333570 A363320
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 23 2019
STATUS
approved