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Search: id:A066756
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| A066756 |
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Smallest number that requires n^3 steps to reach 1 in its Collatz trajectory (counting x/2 and 3x+1 steps). |
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+0
1
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| 1, 2, 6, 65, 673, 342, 2919, 129991, 1590511, 301695657
(list; graph; listen)
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OFFSET
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0,2
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REFERENCES
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R. K. Guy, Problem E16, Unsolved Problems in Number Theory, 2nd edition, Springer-Verlag, NY pp. 215-218
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LINKS
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Index entries for sequences related to 3x+1 (or Collatz) problem
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FORMULA
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Collatz: n = n/d if n even else n = 3*n+1, count the steps until n=1
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EXAMPLE
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sequence(2) = 6 since trajectory of 6 is (6,3,10,5,16,8,4,2,1), 8 steps = 2^3
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CROSSREFS
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Cf. A006577, A066773.
Sequence in context: A139695 A052522 A061999 this_sequence A070872 A055685 A046399
Adjacent sequences: A066753 A066754 A066755 this_sequence A066757 A066758 A066759
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KEYWORD
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more,nonn
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AUTHOR
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Randall L. Rathbun, Jan 18 2002
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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), Apr 12 2002
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