New extremal formally self-dual even codes of length 30
Masaaki Harada, Katsushi Waki · Advances in Mathematics of Communications · 2009
There are extremal formally self-dual even codes which are not selfdualonly for lengths 6, 10, 12, 14, 18, 20, 22, 28 and 30. The only length forwhich the classification has not been done yet is 30. In this note, new extremalformally self-dual even codes of length 30 are constructed using symmetricmatrices.