diff --git a/src/manual-checks/polynomial_after_8_rounds.py b/src/manual-checks/polynomial_after_8_rounds.py
new file mode 100644
index 0000000..c118ce0
--- /dev/null
+++ b/src/manual-checks/polynomial_after_8_rounds.py
@@ -0,0 +1,43 @@
+from sage.all import GF, PolynomialRing
+
+R = PolynomialRing(GF(2), names=[
+    'x00', 'x03', 'x04', 'x05', 'x06', 'x07', 'x10', 'x16', 'x17', 'x21', 'x22', 'g'
+])
+(x00, x03, x04, x05, x06, x07, x10, x16, x17, x21, x22, g) = R.gens()
+
+p = (1 + x00*x04*x05*x10 + x00*x04*x05 + x00*x04*x10 + x00*x04 + x00*x05*x10 + x00*x05 + x00*x07*x10 + x00*x07 + x00*x10*x17 + x00*x17 + x03*x04*x06*x07 + x03*x04*x06*x17 + x03*x04 + x04*x05*x06*x16 + x04*x06*x16 + x05*x06*x16 + x06*x07*x16 + x06*x16*x17 + x06*x16 + x07 + x10 + x16 + x21 + x22 + x00*x04*x05*x06*g + x00*x04*x05*g + x00*x04*x06*g + x00*x04*g + x00*x05*x06*x07*g + x00*x05*x06*x17*g + x00*x05*x06*g + x00*x05*g + x00*x06*x07*g + x00*x06*x17*g + x00*x06*g + x00*x07*g + x00*x10*g + x00*x17*g + x03*x04*x05*x06*g + x03*x05*x06*g + x03*x06*x07*g + x03*x06*x17*g + x03*g + x04*x05*x06*g + x04*x06*g + x06*x16*g + x06*x17*g + g)
+
+def count_monomials(poly):
+    return len(poly.monomials())
+
+p0 = p.subs({x00: 0})
+p1 = p.subs({x00: 1})
+
+p2 = p.subs({x06: 0})
+
+p3 = p0.subs({x06: 0})
+
+print("original polynomial:")
+print("Monomial count:", count_monomials(p))
+print("Polynomial:")
+print(p)
+
+print("\nx00 = 0")
+print("Monomial count:", count_monomials(p0))
+print("Polynomial:")
+print(p0)
+
+print("\nx00 = 1")
+print("Monomial count:", count_monomials(p1))
+print("Polynomial:")
+print(p1)
+
+print("\nx06 = 0")
+print("Monomial count:", count_monomials(p2))
+print("Polynomial:")
+print(p2)
+
+print("\nx00 = 0 and x06 = 0")
+print("Monomial count:", count_monomials(p3))
+print("Polynomial:")
+print(p3)