The exponent of the largest power of 2 which divides a given number .
The values of the ruler function for , 2, ..., are 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, ... (OEIS A001511).
Guy, R. K. "Cycles and Sequences Containing All Permutations as Subsequences." §E22 in Unsolved
Problems in Number Theory, 2nd ed. New York: Springer-Verlag, p. 224,
1994.Sloane, N. J. A. Sequence A001511/M0127
in "The On-Line Encyclopedia of Integer Sequences."
.
The values of the ruler function for 
, 2, ..., are 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, ... (OEIS A001511).
