The extension of some D(4)-pairs

Abstract

In this paper we illustrate the use of the results from [1] proving that $D(4)$-triple $\{a,b,c\}$ with $a<b<a+57\sqrt{a}$ has a unique extension to a quadruple with a larger element. This furthermore implies that $D(4)$-pair $\{a,b\}$ cannot be extended to a quintuple if $a<b<a+57\sqrt{a}$.