sequences.extras: oops. cleanup dumb implementation.
sequences.extras: oops. cleanup dumb implementation.

bpollack/factor,bjourne/factor,tgunr/factor,tgunr/factor,AlexIljin/factor,factor/factor,bjourne/factor,tgunr/factor,bpollack/factor,nicolas-p/factor,bpollack/factor,tgunr/factor,mrjbq7/factor,mrjbq7/factor,bjourne/factor,tgunr/factor,nicolas-p/factor,mrjbq7/factor,bjourne/factor,bpollack/factor,AlexIljin/factor,bjourne/factor,bjourne/factor,nicolas-p/factor,bpollack/factor,nicolas-p/factor,nicolas-p/factor,bpollack/factor,AlexIljin/factor,bjourne/factor,AlexIljin/factor,mrjbq7/factor,factor/factor,tgunr/factor,mrjbq7/factor,nicolas-p/factor,AlexIljin/factor,factor/factor,factor/factor,mrjbq7/factor,AlexIljin/factor,AlexIljin/factor,nicolas-p/factor,bpollack/factor,factor/factor,factor/factor