1 files changed, 12 insertions, 0 deletions

diff --git a/misc_code/ugly_computations/quadratic_class_number.sage b/misc_code/ugly_computations/quadratic_class_number.sage
new file mode 100755
index 0000000..a26dc50
--- /dev/null
+++ b/misc_code/ugly_computations/quadratic_class_number.sage
@@ -0,0 +1,12 @@
+# Determines the proportion of real quadratic fields with odd class number.
+def f(B):
+    sqf = [ b for b in range(2,B) if b%4==1 and is_squarefree(b) ]
+    total_odd = 0
+
+    R.<x> = PolynomialRing(QQ)
+    for a in sqf:
+        if NumberField( x^2 - a, 'c' ).class_number() % 2 == 1:
+            total_odd += 1
+
+    print "=1 mod 4 squarefree integers up to", B, ": ", len(sqf)
+    print "With odd class number:", total_odd