Yuhee, I found something:
P-1 found a factor in stage #1, B1=40000.
4847*2^8387871+1 has a factor: 68788181892978001

But I don't know how to put it into the form.
It is http://www.seventeenorbust.com/sieve ,isn't it?

I am sorry to bother you with all these questions, but on the other side, I think it's not that much work to write a line on the submission-page how to submit. It is mot on MikeH's all sieve site (or I am blind).

(Actually, I tried several quite stupid, I admit, ways to put it in, and got

Factor table setup returned 1
Test table setup returned 1

0 of 1 verified in 0.01 secs.
0 of the results were new results and saved to the database.

So, I think it it is my fault as the input was strange, but as I don't know how to write it... )
Please help me again.