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A066301 a(n) = if n is squarefree then 0 else 1+a(n/rad(n)), where rad=A007947 (squarefree kernel). 3
0, 0, 0, 1, 0, 0, 0, 2, 1, 0, 0, 1, 0, 0, 0, 3, 0, 1, 0, 1, 0, 0, 0, 2, 1, 0, 2, 1, 0, 0, 0, 4, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 1, 0, 0, 3, 1, 1, 0, 1, 0, 2, 0, 2, 0, 0, 0, 1, 0, 0, 1, 5, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 1, 1, 0, 0, 0, 3, 3, 0, 0, 1, 0, 0, 0, 2, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

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

FORMULA

a(n) = A051903(n)-1 for n > 1, a(1) = 0.

EXAMPLE

a(24) = 1+a(24/rad(24)) = 1+a(24/6) = 1+a(4) = 1+(1+a(4/rad(4))) = 1+(1+a(4/2)) = 2+a(2) = 2+0 = 2.

PROG

(PARI) a(n)=if(n>1, vecmax(factor(n)[, 2])-1, 0) \\ Charles R Greathouse IV, Jul 15 2013

(Haskell)

a066301 1 = 0

a066301 n = a051903 n - 1  -- Reinhard Zumkeller, Jul 23 2013~

CROSSREFS

Cf. A005117, A007947, A003557, A008966, A046660, A051903. Not the same as A046660.

Sequence in context: A081221 A280827 A103840 * A046660 A183094 A108730

Adjacent sequences:  A066298 A066299 A066300 * A066302 A066303 A066304

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jan 01, 2002

STATUS

approved

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Last modified November 21 13:53 EST 2017. Contains 295001 sequences.