Sums of distinct integral squares in real quadratic fields

We show that the elements of the ring of integers of real quadratic fields which are sums of integral squares are in fact sums of distinct squares, provided their norm is large enough.

RésuméNous montrons que les entiers totalement positifs de normes suffisamment grandes sont des sommes de carrés distincts dans lʼanneau des entiers des corps réel quadratique.