Asteroid Mining and a Stop at Mars

Anyone good with working orbits.

I'm thinking that there must be some asteroids that we could
encounter on a trip to Mars, or as I like to think of it, on our
trip to the asteroid to set up the automated mining operation, we
can then continue onto a rendevous with Mars.

Can both missions be combined?

Take at look at the orbit of the asteroid 2002 DU3. Of course, I
realize that just because the orbits are close, really means jack
squat. That's why I'm hoping someone on this list how has the math
skill to address the delta-v question and the placement of the
asteroid and Mars question so one could plot a departure from LEo,
arrival at asteroid, and after a given period, continue onto Mars.

http://neo.jpl.nasa.gov/cgi-bin/db?name 02+DU3

I'd be tickled if two missions could be combined into one launch and
one vehicle.