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A095960 Number of divisors of n that are less than the squarefree kernel of n. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

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

CROSSREFS

Cf. A000005, A000040, A005117, A007947, A027750, A032741, A073180.

Sequence in context: A351544 A102396 A344852 * A316314 A183093 A183096

Adjacent sequences:  A095957 A095958 A095959 * A095961 A095962 A095963

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 14 2004

STATUS

approved

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Last modified August 10 00:32 EDT 2022. Contains 356026 sequences. (Running on oeis4.)