On upper bounds for unrestricted binary-error-correcting codes

In this paper improved upper bounds are obtained for
A(n,d)
, the maximum number of binary code vectors in a code of block length
n
and minimum distance
d
. Known bounds are presented in a unified way and then refined, giving improvement over best previously published results in almost all cases. Finally, tabulations of the improved results are given. Asymptotically, the new bounds agree with those given by Elias.