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A327502
a(n) = n/A327501(n), where A327501(n) is the maximum divisor of n that is 1 or not a perfect power.
4
1, 1, 1, 2, 1, 1, 1, 4, 3, 1, 1, 1, 1, 1, 1, 8, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 9, 1, 1, 1, 1, 16, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 32, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 27, 1, 1, 1, 1, 1
OFFSET
1,4
COMMENTS
This maximum divisor is given by A327501.
A multiset is aperiodic if its multiplicities are relatively prime. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). Heinz numbers of aperiodic multisets are numbers that are not perfect powers (A007916).
FORMULA
a(n) = n/A327501(n).
EXAMPLE
The divisors of 36 that are 1 or not a perfect power are {1, 2, 3, 6, 12, 18}, so a(36) = 36/18 = 2.
MATHEMATICA
Table[n/Max[Select[Divisors[n], GCD@@Last/@FactorInteger[#]==1&]], {n, 100}]
PROG
(PARI) A327502(n) = if(n==1, 1, n/vecmax(select(x->((x>1) && !ispower(x)), divisors(n)))); \\ Antti Karttunen, Sep 19 2019 (after program given by Michel Marcus for A327501)
CROSSREFS
See link for additional cross-references.
Sequence in context: A140130 A337087 A321312 * A354090 A362826 A220632
KEYWORD
nonn,look
AUTHOR
Gus Wiseman, Sep 16 2019
STATUS
approved