Another update from ingydotnet^djgoku

Task/Arithmetic-Rational/Julia/arithmetic-rational.julia

@@ -0,0 +1,24 @@
+function isperfect{T<:Integer}(n::T)
+    !isprime(n) || return false
+    tal = 1//n
+    hi = isqrt(n)
+    if hi^2 == n
+        tal += 1//hi
+        hi -= 1
+    end
+    for i in 2:hi
+        (d, r) = divrem(n, i)
+        if r == 0
+            tal += (1//i + 1//d)
+        end
+    end
+    return tal == 1//1
+end
+
+lo = 2
+hi = 2^19
+println("Searching for perfect numbers from ", lo, " to ", hi, ".")
+for i in 2:2^19
+    isperfect(i) || continue
+    println(@sprintf("%8d", i))
+end