OFFSET
2,1
COMMENTS
EXAMPLE
Example (a(4)=9): 9-3=6, 6-2=4, 4-2=2, 2-2=0; iterations has 4 steps and number 9 is the largest number with such result.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Feb 15 2010
EXTENSIONS
Edited by R. J. Mathar, Mar 11 2010
STATUS
approved