diff --git a/app.js b/app.js
index ad9a93a..c2ea37e 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 trib(n){
+    if(memo.has(n)) {
+        return memo.get(n);
+    }
+    const value = trib(n-1) + trib(n-2) + trib(n-3);
+    memo.set(n,value);
+    return value;
+}
+const length = 4;
+for (let i = 0; i <= length; i++) {
+    console.log(trib(i));
+}
\ No newline at end of file