diff --git a/Week03/pyramid_gokhan_koray_bulbul.py b/Week03/pyramid_gokhan_koray_bulbul.py
new file mode 100644
index 00000000..d975e649
--- /dev/null
+++ b/Week03/pyramid_gokhan_koray_bulbul.py
@@ -0,0 +1,9 @@
+def calculate_pyramid_height(number_of_blocks):
+    # Input precautions
+    if (not isinstance(number_of_blocks, int)) or (number_of_blocks < 0):
+        raise TypeError("number_of_blocks must be a non-negative whole integer.")
+    
+    height = 1
+    while True:
+        if(number_of_blocks := number_of_blocks - height) <= height: return height
+        height += 1
diff --git a/Week03/sequences_gokhan_koray_bulbul.py b/Week03/sequences_gokhan_koray_bulbul.py
new file mode 100644
index 00000000..9eb2d437
--- /dev/null
+++ b/Week03/sequences_gokhan_koray_bulbul.py
@@ -0,0 +1,21 @@
+def remove_duplicates(seq: list) -> list:
+    # returning list(set(seq)) would not preserve order
+    unique_set = set()
+    result = []
+    for item in seq:
+        if item not in unique_set:
+            result.append(item)
+            unique_set.add(item)
+    return result
+    
+def list_counts(seq: list) -> dict:
+    occurance_dict = dict.fromkeys(seq, 0)
+    for item in seq:
+        occurance_dict[item] += 1      
+    return occurance_dict
+
+def reverse_dict(d: dict) -> dict:
+    reversed_dict = dict() 
+    for key, value in d.items():
+        reversed_dict[value] = key
+    return reversed_dict