Really? I didn't know there were any large primes one away from a power-of-ten number (not sure if I said that right)...A number with almost all zeros.

Maybe there's actually plenty of them (not sure)? Although I'm sure all large primes are hard to find. Did you find it with GIMPS, or some other method?

It's pretty amazing - good work!

Thanks. I found a bunch of large primes of that form. I was "showing off" with my 5.0 GHz supercomputers I had access to. Just to prove they weren't "flukes" I found two prime numbers with each coefficient.

And no, I was not a part of GIMPS, this was a solo effort.

7 x 10 raised to the ridiculous + 1 has two different primes

6 x 10 raised to the ridiculous + 1 has two different primes

I even used 2 raised to the power of 64 - 189 as a coefficient. I proved, separately, that 2^64 - 189 is the largest prime number less than 2^64 that can be used as a coefficient for a 10^n + 1 sequence and still generate a prime number.