Addendum to “computably enumerable sets and quasi-reducibility”

ANNALS OF PURE AND APPLIED LOGIC ELSEVIEK

Annals

Addendum

of Pure

and Applied

Logic

98

( 1999)

295

to “Computably enumerable quasi-reducibility” R. Downey,

sets and

G. LaForte *, A. Nies

Received 20 November Communicated by R.I.

1998 Soare

The authors wish to acknowledge that Theorem 3 in their paper, stating that there can be no nontrivial decomposition of a semirecursive set in the Q-degrees, was obtained independently by R. Sh. Omanadze.

* Corresponding

author.

016%0072/99/$ - see front PII: SOl68-0072(98)00061-X

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