Amicable pairs
func propdivsum(n) {
n.sigma - n
}
for i in (1..20000) {
var j = propdivsum(i)
say "#{i} #{j}" if (j>i && i==propdivsum(j))
}
Output:
220 284
1184 1210
2620 2924
5020 5564
6232 6368
10744 10856
12285 14595
17296 18416