Firstly, I wasn't sure whether a nixie thread should go under displays or LEDs/multiplexing, so I plumped for here. I reckon I can get away with it, I've been here a while but right now I'm feeling like a complete n00b and that I haven't learnt anything in the eight or so months I've been messing around with arduinos. Anyway...
I have a nixie tube socket wired up to a breadboard (with a nixie in it). I have suitable 180v, 12v and 5v supplies. I have a 74141 (although it's russian so it's labelled differently. I have checked and the pin out is identical).
I have tested the nixie by running individual pins (not using the 74141) and it works fine.
I then wired up the chip as per the usual pinout (example), using 5v for the Vcc and popping the four logic pins into the arduino. I then knocked up a basic sketch which switched the pins low/high according to the number, aiming to go from 0 to 10 in sequence.
This is where I hit a problem. Numbers stayed illuminated. I'm afraid I wasn't paying enough attention to spot whether some or all of the previously illuminated numbers stayed lit up (they weren't going in the correct order but that shouldn't matter). I removed the arduino and some numbers stayed illuminated (powering off before doing anything). I set all the data pins to ground, no change. I removed the Vcc, no change. I tied the Vcc to ground, no change. I removed the data pins and Vcc, no change. I removed the ground pin - no output. Put it back, no change. The same digits were lit up.
Have I broken the 74141? Is there something I need to do to clear the chip when changing numbers?