OFFSET
1,3
COMMENTS
It appears that k < n/4. Record values of k occur when n=2p, where p is a prime with primitive root 2 (A001122). In this case, k=(p-1)/2.
LINKS
T. D. Noe, Table of n, a(n) for n=1..1000
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Oct 25 2007
STATUS
approved