OFFSET
0,3
COMMENTS
Number of steps needed to reach zero when starting from k = 2*n and repeatedly applying the map that replaces k by k - d(k), where d(k) is the number of divisors of k (A000005).
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..10000
FORMULA
a(n) = A155043(2*n).
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 02 2015
STATUS
approved