Carmichael 3 strong pseudoprimes: Difference between revisions

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 =={{header|D}}==
+<lang d>enum mod = (in int n, in int m) pure nothrow => ((n % m) + m) % m;
-This uses the third D entry of the Sieve of Eratosthenes Task.
-<lang d>import std.stdio, sieve_of_eratosthenes3;
-int mod(in int n, in int m) pure nothrow {
+bool isPrime(in uint n) pure nothrow {
-  return ((n % m) + m) % m;
+  if (n == 2 || n == 3)
+    return true;
+  else if (n < 2 || n % 2 == 0 || n % 3 == 0)
+    return false;
+  for (uint div = 5, inc = 2; div ^^ 2 <= n;
+     div += inc, inc = 6 - inc)
+    if (n % div == 0)
+      return false;
+  return true;
 }
 void main() {
+  import std.stdio;
   foreach (immutable p; 2 .. 62) {
-    if (!p.IsPrime) continue;
+    if (!p.isPrime) continue;
     foreach (immutable h3; 2 .. p) {
       immutable g = h3 + p;
@@ Line 95: / Line 104: @@
           continue;
         immutable q = 1 + (p - 1) * g / d;
-        if (!q.IsPrime) continue;
+        if (!q.isPrime) continue;
         immutable r = 1 + (p * q / h3);
-        if (!r.IsPrime || (q * r) % (p - 1) != 1) continue;
+        if (!r.isPrime || (q * r) % (p - 1) != 1) continue;
         writeln(p, " x ", q, " x ", r);
       }