Initial data commit

Task/Proper-divisors/Nim/proper-divisors.nim

@@ -0,0 +1,42 @@
+import strformat
+
+proc properDivisors(n: int) =
+  var count = 0
+  for i in 1..<n:
+    if n mod i == 0:
+      inc count
+      write(stdout, fmt"{i} ")
+  write(stdout, "\n")
+
+proc countProperDivisors(n: int): int =
+  var nn = n
+  var prod = 1
+  var count = 0
+  while nn mod 2 == 0:
+    inc count
+    nn = nn div 2
+  prod *= (1 + count)
+  for i in countup(3, n, 2):
+    count = 0
+    while nn mod i == 0:
+      inc count
+      nn = nn div i
+    prod *= (1 + count)
+  if nn > 2:
+    prod *= 2
+  prod - 1
+
+for i in 1..10:
+  write(stdout, fmt"{i:2}: ")
+  properDivisors(i)
+
+var max = 0
+var maxI = 1
+
+for i in 1..20000:
+  var v = countProperDivisors(i)
+  if v >= max:
+    max = v
+    maxI = i
+
+echo fmt"{maxI} with {max} divisors"