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A324931
Integers in the list of quotients of positive integers by their product of prime indices.
17
1, 2, 4, 3, 8, 6, 16, 12, 7, 5, 32, 9, 24, 14, 10, 64, 18, 48, 28, 20, 128, 36, 19, 13, 21, 15, 96, 27, 56, 40, 256, 72, 38, 26, 11, 42, 30, 192, 54, 112, 17, 80, 512, 144, 76, 52, 22, 84, 60, 384, 49, 23, 35, 53, 108, 37, 224, 25, 57, 39, 34, 160, 63, 1024
OFFSET
1,2
COMMENTS
These quotients are given by A324932(n)/A324933(n).
This is a permutation of the positive integers, with inverse A324934.
FORMULA
a(n) = A324850(n)/A003963(A324850(n)).
EXAMPLE
The sequence of quotients n/A003963(n) begins: 1, 2, 3/2, 4, 5/3, 3, 7/4, 8, 9/4, 10/3, 11/5, 6, 13/6, 7/2, 5/2, 16, ...
MATHEMATICA
Select[Table[n/Times@@Cases[If[n==1, {}, FactorInteger[n]], {p_, k_}:>PrimePi[p]^k], {n, 100}], IntegerQ]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 21 2019
STATUS
approved