\x09 \x09 \x09\x09\x09\x09\x09 \x09 \x09 \x09\x09\x09 \x09 \x09 \x09 \x09 \x09 \x09
Note that non-ascii characters in the above source code will be escaped (such as \x9f).
Disassemble:
mark null push +1(1b) dup dup geti retr dup push +2(2b) mod add add puti push +10(4b) putc jump null