OFFSET
1,2
COMMENTS
Conjecture: the sequence is defined for all n.
a(10) <= 281594003343201014885689. - David Wasserman, Dec 13 2005
EXAMPLE
a(3) = 2093 = 7*13*23 with divisors >1: 7, 13, 23, 91, 161, 299 and 2093, which are prefix-free in binary: 111, 1101, 10111, 1011011, 10100001, 100101011 and 100000101101.
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Reinhard Zumkeller, Nov 26 2003
EXTENSIONS
More terms from David Wasserman, Dec 13 2005
STATUS
approved