Fix sequences docs for change-nth stack effect and example needed using section
Fix sequences docs for change-nth stack effect and example needed using section

factor/factor,AlexIljin/factor,AlexIljin/factor,bjourne/factor,bpollack/factor,bpollack/factor,bjourne/factor,dch/factor,sarvex/factor-lang,mrjbq7/factor,dch/factor,sarvex/factor-lang,mrjbq7/factor,nicolas-p/factor,dch/factor,sarvex/factor-lang,factor/factor,sarvex/factor-lang,dch/factor,sarvex/factor-lang,bpollack/factor,mrjbq7/factor,bpollack/factor,nicolas-p/factor,AlexIljin/factor,dch/factor,bpollack/factor,bjourne/factor,tgunr/factor,slavapestov/factor,tgunr/factor,sarvex/factor-lang,tgunr/factor,bpollack/factor,mrjbq7/factor,factor/factor,factor/factor,AlexIljin/factor,mrjbq7/factor,tgunr/factor,slavapestov/factor,nicolas-p/factor,nicolas-p/factor,factor/factor,slavapestov/factor,nicolas-p/factor,tgunr/factor,nicolas-p/factor,bjourne/factor,factor/factor,mrjbq7/factor,slavapestov/factor,tgunr/factor,bjourne/factor,bjourne/factor,slavapestov/factor,slavapestov/factor,bjourne/factor,nicolas-p/factor,slavapestov/factor,AlexIljin/factor,AlexIljin/factor,AlexIljin/factor,sarvex/factor-lang,dch/factor,bpollack/factor