1,1
See A118141 for definitions and references.
If an odd number m appears then so does 2m+1.
Sequence in context: A076065 A176115 A066898 * A001350 A077238 A185507
Adjacent sequences: A118140 A118141 A118142 * A118144 A118145 A118146
nonn
D. E. Knuth, May 11 2006