Ayşe ALACA, Şaban ALACA, Kenneth Stuart WILLIAMS

Representation numbers of seven quaternary quadratic forms each in a genus consisting of only two classes

The purpose of this paper is to present some examples of positive-definite integral nondiagonal quaternary quadratic forms whose representation numbers can be determined explicitly using the theory of modular forms. Very few such examples appear in the literature. The seven forms presented were selected because they each belong to a genus containing exactly two form classes for which the single genus mate is a diagonal form whose representation number has been determined recently.

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