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A255308
Number of times log_2 can be applied to n until the result is not a power of 2. Here log_2 means the base-2 logarithm.
4
0, 1, 2, 0, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
0,3
COMMENTS
Multiplicative because only powers of two have a nonzero value. - Andrew Howroyd, Jul 27 2018
LINKS
FORMULA
a(n) = 1 + a(log_2(n)) if n is a power of 2, 0 otherwise.
PROG
(PARI) a(n) = if(n < 1, 0, my(e=valuation(n, 2)); if(n == 2^e, 1 + a(e), 0)) \\ Andrew Howroyd, Jul 27 2018
CROSSREFS
One less than A293668.
Sequence in context: A209640 A080300 A116864 * A079302 A138806 A181105
KEYWORD
nonn,easy,mult
AUTHOR
Paul Boddington, Feb 20 2015
EXTENSIONS
Extended up to a(128) by Antti Karttunen, Sep 30 2018
STATUS
approved