This is pdfTeX, Version 3.1415926-1.40.11 (TeX Live 2010) (format=pdflatex 2010.7.21)  25 APR 2011 13:50
entering extended mode
 restricted \write18 enabled.
 %&-line parsing enabled.
**sagebook.

! Emergency stop.
<*> sagebook.
             
End of file on the terminal!

 
Here is how much of TeX's memory you used:
 4 strings out of 493747
 103 string characters out of 3143546
 49070 words of memory out of 3000000
 3397 multiletter control sequences out of 15000+200000
 3640 words of font info for 14 fonts, out of 3000000 for 9000
 714 hyphenation exceptions out of 8191
 0i,0n,0p,1b,6s stack positions out of 5000i,500n,10000p,200000b,50000s
!  ==> Fatal error occurred, no output PDF file produced!