A075104 Greatest common divisor of n and integer part of log_2(n).

1, 1, 1, 2, 1, 2, 1, 1, 3, 1, 1, 3, 1, 1, 3, 4, 1, 2, 1, 4, 1, 2, 1, 4, 1, 2, 1, 4, 1, 2, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 3, 2

Offset

1,4

Links

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

Formula

a(n) = gcd(n, A000523(n)).

Mathematica

Table[GCD[n, IntegerPart[Log[2, n]]], {n, 110}] (* Harvey P. Dale, Apr 21 2016 *)

Prog

(Haskell)
a075104 n = gcd n $ a000523 n  -- Reinhard Zumkeller, Jul 08 2014

Crossrefs

Cf. A000523, A075105, A075106.

Sequence in context: A261095 A394052 A249809 * A253667 A360189 A368210

Adjacent sequences: A075101 A075102 A075103 * A075105 A075106 A075107

Keyword

nonn

Author

Reinhard Zumkeller, Sep 02 2002

Status

approved