"Depends."
If you collected all the light from those three 10 lm lights exactly in the some spot/area as the 30 lm light, the answer would be basically yes. Lumen is basically a measure of "how much light", like Ampere for electricity or cubic meters for volume, it doesn't say anything about brightness at all, if you are nitpicky. Brightness is basically how much light can you get to your eye or inside the area you light up, so that will be a combination of the focussing system and the total output of the flashlight (lm), and Candela is a better unit.
And, to move onto subjective brightness, the eye is not a linear transduser, whereas lumen is a linear unit scaling with the energy output. The eye works fine within a range where the highest working conditions has 100 000 more light than the lowest working conditions if I remember my classes correctly. So, when a human says "twice as bright", it may require more than twice as much energy to get there.
The Wikipedia article is a pretty easy read:
http://en.wikipedia.org/wiki/Lumen_(unit)Edit: I just wanted to specify, part of the huge dynamic range of the eye, is obviously the pupils ability to shield the receptors from too extreme inputs, it's not only smart signal encoding and signal transformations.
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