Data update

Task/Totient-function/Pluto/totient-function.pluto

@@ -0,0 +1,33 @@
+local function totient(n)
+    local tot = n
+    local i = 2
+    while i * i <= n do
+        if n % i == 0 then
+            while n % i == 0 do n //= i end
+            tot -=  tot // i
+        end
+        if i == 2 then i = 1 end
+        i += 2
+    end
+    if n > 1 do tot -= tot // n end
+    return tot
+end
+
+print(" n  phi   prime")
+print("---------------")
+local count = 0
+for n = 1, 25 do
+    local tot = totient(n)
+    local isPrime = (n - 1) == tot
+    if isPrime then ++count end
+    print(string.format("%2d   %2d   %s", n, tot, isPrime))
+end
+print("\nNumber of primes up to 25     = " .. count)
+for n = 26, 100_000 do
+    local tot = totient(n)
+    if tot == n - 1 then ++count end
+    if n == 100 or n == 1_000 or n % 10_000 == 0 then
+        local ns = string.format("%-6d", n)
+        print($"\nNumber of primes up to {ns} = {count}")
+    end
+end