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A120425 a(n) = maximum value among all k where 1<=k<=n of GCD(k,ceiling(n/k)). 0
1, 1, 2, 2, 2, 2, 3, 3, 3, 2, 2, 2, 4, 4, 4, 4, 3, 3, 3, 3, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 6, 6, 6, 6, 6, 6, 4, 4, 4, 4, 5, 5, 7, 7, 7, 7, 7, 7, 7, 5, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 8, 6, 6, 6, 6, 6, 6, 6, 6, 9, 9, 9, 9, 9, 9, 9, 9, 9, 5, 5, 5, 7, 7, 7, 7, 7, 7, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

EXAMPLE

For n = 10, we have the pairs {k,ceiling(n/k)} of {1,10},{2,5},{3,4},{4,3},{5,2},{6,2},{7,2},{8,2},{9,2},{10,1}. The GCD's of these 10 pairs are 1,1,1,1,1,2,1,2,1,1. Of these, 2 is the largest. So a(10) = 2.

MATHEMATICA

Table[Max[Table[GCD[k, Ceiling[n/k]], {k, 1, n}]], {n, 1, 100}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jul 22 2006

CROSSREFS

Sequence in context: A055894 A168557 A194320 * A104186 A184320 A092363

Adjacent sequences:  A120422 A120423 A120424 * A120426 A120427 A120428

KEYWORD

nonn

AUTHOR

Leroy Quet Jul 12 2006

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jul 22 2006

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Last modified February 15 09:35 EST 2012. Contains 205753 sequences.