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A327402
Quotient of n over the maximum stable divisor of n.
1
1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 1, 2, 1, 1, 1, 2, 1, 4, 3, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 1, 1, 2, 1, 4, 1, 2, 3, 5, 1, 6, 1, 4, 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 1, 7, 3, 2, 1, 4, 1, 2, 7, 1, 5, 2, 1, 4, 1, 2, 1, 8, 1, 2, 1, 4, 1, 6, 1, 5, 1, 2, 1, 12, 1, 2, 3
OFFSET
1,6
COMMENTS
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. A number is stable if its distinct prime indices are pairwise indivisible. Stable numbers are listed in A316476.
FORMULA
a(n) = n/A327393(n).
EXAMPLE
The stable divisors of 60 are {1, 2, 3, 4, 5, 15}, so a(60) = 60/15 = 4.
MATHEMATICA
stableQ[u_, Q_]:=!Apply[Or, Outer[#1=!=#2&&Q[#1, #2]&, u, u, 1], {0, 1}];
Table[n/Max[Select[Divisors[n], stableQ[PrimePi/@First/@FactorInteger[#], Divisible]&]], {n, 100}]
CROSSREFS
See link for additional cross-references.
Sequence in context: A340035 A185147 A206921 * A123529 A140747 A330757
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 15 2019
STATUS
approved