Add primality tests.

src/algorithms/math/primality-test/trialDivision.js

@@ -0,0 +1,28 @@
+/**
+ * @param {number} number
+ * @return {boolean}
+ */
+export default function trialDivision(number) {
+  if (number <= 0) {
+    // If number is less then one then it isn't prime by definition.
+    return false;
+  } else if (number <= 3) {
+    // All numbers from 1 to 3 are prime.
+    return true;
+  }
+
+  // If the number is not divided by 2 then we may eliminate all further even dividers.
+  if (number % 2 === 0) {
+    return false;
+  }
+
+  // If there is no dividers up to square root of n then there is no higher dividers as well.
+  const dividerLimit = Math.sqrt(number);
+  for (let divider = 3; divider <= dividerLimit; divider += 2) {
+    if (number % divider === 0) {
+      return false;
+    }
+  }
+
+  return true;
+}