Revisions to Proper Divisor mash-up

added 46 characters in body

Source Link

edited Jun 25, 2017 at 16:58

Haskell, 48 4646 43 bytes

f 2=1
f n=last[d|d<-[1.n=until((<1).n-1],mod n d<1]+f)pred(n-1)+f(n-1)

Edit: @rogaos saved two bytes. Thanks!

Edit II: ... and @xnor another 3 bytes.

f 2=1
f n=last[d|d<-[1..n-1],mod n d<1]+f(n-1)

Edit: @rogaos saved two bytes. Thanks!

f 2=1
f n=until((<1).mod n)pred(n-1)+f(n-1)

Edit: @rogaos saved two bytes. Thanks!

Edit II: ... and @xnor another 3 bytes.

added 53 characters in body

Source Link

edited Jun 24, 2017 at 21:46

f n=sum[last[d|d<2=1
f n=last[d|d<-[1..xn-1],mod xn d<1]|x<d<1]+f(n-[2..n]]1)

Edit: @rogaos saved two bytes. Thanks!

f n=sum[last[d|d<-[1..x-1],mod x d<1]|x<-[2..n]]

f 2=1
f n=last[d|d<-[1..n-1],mod n d<1]+f(n-1)

Edit: @rogaos saved two bytes. Thanks!

Source Link

created Jun 24, 2017 at 12:00

f n=sum[last[d|d<-[1..x-1],mod x d<1]|x<-[2..n]]