diff --git a/app.js b/app.js
index ad9a93a7..b42ef5cb 100644
--- a/app.js
+++ b/app.js
@@ -1 +1,18 @@
 'use strict';
+const memo = new Map();
+memo.set(0, 0);
+memo.set(1, 0);
+memo.set(2, 1);
+
+function fib(n) {
+  if (memo.has(n)) {
+    return memo.get(n);
+  }
+  const value = fib(n - 1) + fib(n - 2) + fib(n - 3);
+  memo.set(n, value);
+  return value;
+}
+const length = 40;
+for (let i = 0; i <= length; i++) {
+  console.log(fib(i));
+}
\ No newline at end of file