Memoize small primes list
Memoize small primes list

This makes "benchmark.binary-search" work again in a reasonable time.
slavapestov/factor,erg/factor,ehird/factor,tgunr/factor,AlexIljin/factor,mrjbq7/factor,littledan/Factor,mrjbq7/factor,seckar/factor,Keyholder/factor,sarvex/factor-lang,factor/factor,bpollack/factor,Keyholder/factor,nicolas-p/factor,factor/factor,bjourne/factor,dch/factor,sarvex/factor-lang,ceninan/factor,sarvex/factor-lang,dharmatech/factor,kingcons/factor,cataska/factor,slavapestov/factor,mcandre/factor,AlexIljin/factor,factor/factor,bpollack/factor,factor/factor,nicolas-p/factor,bjourne/factor,kingcons/factor,mcandre/factor,jwmerrill/factor,littledan/Factor,slavapestov/factor,jwmerrill/factor,tgunr/factor,ehird/factor,sarvex/factor-lang,mcandre/factor,AlexIljin/factor,littledan/Factor,nicolas-p/factor,sarvex/factor-lang,bjourne/factor,mcandre/factor,jwmerrill/factor,sarvex/factor-lang,AlexIljin/factor,bpollack/factor,dch/factor,ceninan/factor,bjourne/factor,erg/factor,seckar/factor,ceninan/factor,erg/factor,slavapestov/factor,mrjbq7/factor,mrjbq7/factor,cataska/factor,bpollack/factor,erg/factor,bpollack/factor,mcandre/factor,tgunr/factor,bjourne/factor,tgunr/factor,bjourne/factor,littledan/Factor,bpollack/factor,AlexIljin/factor,factor/factor,dch/factor,ceninan/factor,bjourne/factor,mrjbq7/factor,slavapestov/factor,cataska/factor,Keyholder/factor,nicolas-p/factor,dch/factor,dch/factor,seckar/factor,dharmatech/factor,kingcons/factor,ehird/factor,nicolas-p/factor,dharmatech/factor,tgunr/factor,nicolas-p/factor,factor/factor,mrjbq7/factor,erg/factor,erg/factor,mcandre/factor,AlexIljin/factor,bpollack/factor,sarvex/factor-lang,erg/factor,dch/factor,slavapestov/factor,mcandre/factor,nicolas-p/factor,AlexIljin/factor,tgunr/factor,slavapestov/factor,kingcons/factor,cataska/factor