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A095960
Number of divisors of n that are less than the squarefree kernel of n.
3
0, 1, 1, 1, 1, 3, 1, 1, 1, 3, 1, 4, 1, 3, 3, 1, 1, 3, 1, 4, 3, 3, 1, 4, 1, 3, 1, 4, 1, 7, 1, 1, 3, 3, 3, 4, 1, 3, 3, 5, 1, 7, 1, 4, 4, 3, 1, 4, 1, 3, 3, 4, 1, 3, 3, 5, 3, 3, 1, 10, 1, 3, 4, 1, 3, 7, 1, 4, 3, 7, 1, 4, 1, 3, 3, 4, 3, 7, 1, 5, 1, 3, 1, 10, 3, 3, 3, 5, 1, 9, 3, 4, 3, 3, 3, 4, 1, 3, 4, 4, 1, 7
OFFSET
1,6
LINKS
FORMULA
a(A005117(n)) = A032741(A005117(n)).
a(A000040(n)) = 1.
EXAMPLE
n = 40 = 5*2^3, rad(40) = 10: a(40) = #{d:d<10} = #{1,2,4,5,8} = 5.
MATHEMATICA
a[n_] := DivisorSum[n, 1 &, # < Times @@ FactorInteger[n][[;; , 1]] &]; Array[a, 100] (* Amiram Eldar, Jul 09 2022 *)
PROG
(Haskell)
a095960 n = length [x | x <- a027750_row n, x < a007947 n]
-- Reinhard Zumkeller, Sep 10 2013
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 14 2004
STATUS
approved