diff --git a/src/main/scala/main.scala b/src/main/scala/main.scala
index c6288f2..70ef690 100644
--- a/src/main/scala/main.scala
+++ b/src/main/scala/main.scala
@@ -59,3 +59,27 @@ def binKoeffRek(m:Int,n:Int):Int = {
   else return m * binKoeffRek(m - 1, n - 1) / n
 }
 
+
+//Aufgabe 5
+
+def triagnles(n:Int):Int = {
+
+  // mistake is in sum it always returns 1
+
+  def sum(i: Int, n: Int): Int = {
+    if (i <= n) then{
+      //      println("Test1")
+      return (n-i)+sum(i+2,n)
+    }
+    else {
+      1
+    }
+  }
+  //  println("Test2")
+  if (n == 1) {
+    return 1
+  } else {
+    //return n
+    return triagnles(n - 1) + ((n * (n + 1)) / 2) + sum(1,n)
+  }
+}