sequence_1_0001.jpg
sequence_1_0002.jpg
sequence_1_0003.jpg
...

sequence_1_0001.hmf
sequence_1_0002.hmf
sequence_1_0003.hmf
...

sequence_2_0001.jpg
sequence_2_0002.jpg
sequence_2_0003.jpg
...

sequence_2_0001.hmf
sequence_2_0002.hmf
sequence_2_0003.hmf
...

rm sequence_1*.hmf

for c in {0..9}; do rm sequence_1_"$c"*.hmf; done
rm sequence_1*.hmf  # catch-all case

find . -maxdepth 1 -type f -name 'sequence_1*.hmf' -delete

rm sequence_1_{0000..0999}.hmf
rm sequence_1_{1000..1999}.hmf
rm sequence_1_{2000..2999}.hmf
...