NUMBER OF SQUFNITS IN A BIQUADRATIC FIELD

Abstract

Let U be the full unit group in the biquadratic field ℚ(√c, √d, √e) where c and d are square free integers and e is the square free part of cd. Let H be the unit group generated by the fundamental units of ℚ(√c), ℚ(√d) and ℚ(√e). The objective of this paper is to show that the group index [U: H] is not divisible by 8.