What is the smallest prime of the form $410333333333...$ ? It should have more than $10,000$ digits.
[added from answer posted 2013 May 26 at 20:52 by Peter]
I thought it would be clear, but it seems not to be. Of course, after $410$, only $3$'s should follow. Otherwise, it would be very easy to find primes. I checked the numbers up to about $10,000$ digits, but of course, I would be glad if someone checks this, too.
I do not understand the question, WHY this number is interesting for me. Mersenne primes are not so much more interesting, but recently a prize of $100,000\$ $was payed for a community finding a $17$-million-digit mersenne prime. I would have better ideas what to do with all this money ...