Some sources say : One cycle = consumption of 3 CO2
Some other sources say : One cycle = consumption of 1 CO2 [This is the more frequent definition]
Anyway, the important point is that for one molecule of glucose [or 2 molecules of G3p], 6 CO2, 18 ATP, and 12 NADPH are used. I would say we need 6* cycles for one molecule of glucose [based on the more frequent definition]'
I hope this helps