diff --git a/src/sage/schemes/hyperelliptic_curves/hyperelliptic_finite_field.py b/src/sage/schemes/hyperelliptic_curves/hyperelliptic_finite_field.py index ad5e02a75a1..8316d881fcd 100644 --- a/src/sage/schemes/hyperelliptic_curves/hyperelliptic_finite_field.py +++ b/src/sage/schemes/hyperelliptic_curves/hyperelliptic_finite_field.py @@ -1132,7 +1132,10 @@ def cardinality_exhaustive(self, extension_degree=1, algorithm=None): # begin with points at infinity (on the smooth model) if g == 1: # elliptic curves always have one smooth point at infinity - a += 1 + if K.degree() % 2: + a += 1 + elif K.characteristic() != 2: + a += 1 + legendre_symbol(a, K.cardinality()) else: # g > 1 # solve y^2 + y*h[g+1] == f[2*g+2], i.e., y^2 + r*y - s == 0