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A064415
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a(1) = 0, a(n) = iter(n) if n is even, a(n) = iter(n)-1 if n is odd, where iter(n) = A003434(n) = smallest number of iterations of Euler totient function phi needed to reach 1.
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3
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0, 1, 1, 2, 2, 2, 2, 3, 2, 3, 3, 3, 3, 3, 3, 4, 4, 3, 3, 4, 3, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 5, 4, 5, 4, 4, 4, 4, 4, 5, 5, 4, 4, 5, 4, 5, 5, 5, 4, 5, 5, 5, 5, 4, 5, 5, 4, 5, 5, 5, 5, 5, 4, 6, 5, 5, 5, 6, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 4, 6, 6, 5, 6, 5, 5, 6, 6, 5, 5, 6, 5, 6, 5, 6, 6, 5, 5, 6, 6, 6, 6, 6, 5
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
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FORMULA
| For all integers m >0 and n>0 a(m*n)=a(m)+a(n). The function a(n) is completely additive. The smallest integer q which satisfy the equation a(q)=n is 2^q, the greatest is 3^q. For all integers n>0, the counter image off n, a^-1(n) is finite.
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PROG
| (Haskell)
a064415 1 = 0
a064415 n = a003434 n - n `mod` 2 -- Reinhard Zumkeller, Sep 18 2011
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CROSSREFS
| Cf. A000010, A003434, A064416.
Cf. A054725. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 02 2008]
Sequence in context: A167439 A125173 A054725 * A086833 A010764 A029383
Adjacent sequences: A064412 A064413 A064414 * A064416 A064417 A064418
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KEYWORD
| nonn
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AUTHOR
| Christian WEINSBERG (cweinsbe(AT)fr.packardbell.org), Sep 30 2001
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EXTENSIONS
| More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Jul 22 2002
Definition corrected by Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Sep 18 2011
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