Hm... It will be sufficient, but probably hardly because you are more than likely going to be losing lumens unless it's in a fully reflective grow cab/box. You're going to need to direct all the light you possibly can at the plant. Growth might be a little slow, but as a seedling it will be fine. Try to place that sucker as close as you possibly can without burning the seedling up. I have used a single 15 watt (950 lumen) to grow a seedling, but I'm not sure if it was for 2 weeks, that seems kind of long to be using such low lumens, so I'm not positive the 23 watter will be good or not, but if anything, it's light at least.
You might be better off putting the plant on a window sill and let the sun get at it.