οὐκοῦν, ad significandam conclusionem, fere i q οὖν Φθ1. 251a16. Πγ10. 1281 a29. η9. 1329 a16. K3. 1 b14. 5. 2 a37,b2, 3 a5. 6. 5 a10, b20.
Liddell-Scott-Jones: A Greek-English lexicon
οὐκοῦν, Dor. οὐκῶν, Adv., composed, like οὔκουν, of οὐκ and οὖν, but differing in meaning and accent, cf. A.D.Conj.257.18sqq., Hdn.Gr.1.516, Phryn.PSp.98B. I. in questions, inviting assent to an inference, or to an addition to what has already received assent, οὐκοῦν δοκεῖ σοι ..
;
you think
then, do you not
, that ..? X.Cyr.2.4.15, Mem.1.4.5, cf. 4.2.20, Pl.Prt.332b, 360b-d, Cra.416c, etc.: with hortatory subj., οὐκοῦν καὶ ἄλλους σε φῶμεν δυνατὸν εἶναι ποιεῖν (sc. ῥήτορας ἀγαθούσ)
;
Id.Grg.449b: folld. by οὐ when a neg. answer is invited, οὐκοῦν οὐκ ἂν εἴη τὸ μὴ λυπεῖσθαί ποτε ταὐτὸν τῷ χαίρειν