The existence of a quantum [[28, 12, 6]] code was one of the few cases for codes of length n ≤ 30 that was left open in the seminal paper by Calderbank, Rains, Shor, and Sloane [2]. The main result of this paper is the construction of the first optimal linear quaternary [28, 20, 6] code which contains its Hermitian dual code and yields the first optimal quantum [[28, 12, 6]] code. 2010 MSC: 94B...

Code generators based on bottom-up rewrite systems (BURS) are automatically generated from machinedescription grammars. They produce locally optimal code for expression trees, but their tables are large and require compile-time interpretation. This paper describes a program that compiles BURS tables into a combination of hard code and data. Hard-coding exposed important opportunities for compre...

We use exhaustive computer searches to show that there are exactly 36 codewords in an optimal ternary (11, 7) code and exactly 13 codewords in an optimal ternary (14, 10) code. We also enumerate optimal ternary (14, 10) codes and show that there are exactly 6151 inequivalent such