6 letter words:
proper10,
5 letter words:
preop9,
repro7,
roper7,
4 letter words:
pepo8,
perp8,
pope8,
prep8,
prop8,
repp8,
pore6,
repo6,
rope6,
3 letter words:
pep7,
pop7,
ope5,
per5,
pro5,
rep5,
err3,
ore3,
roe3,
2 letter words:
op4,
pe4,
er2,
oe2,
or2,
re2,