# Adequate pointclass

In the mathematical field of descriptive set theory, a **pointclass** can be called **adequate** if it contains all recursive pointsets and is closed under recursive substitution, bounded universal and existential quantification and preimages by recursive functions.^{[1]}^{[2]}

## References

- ↑ Moschovakis, Y. N. (1987),
*Descriptive Set Theory*, Studies in Logic and the Foundations of Mathematics, Elsevier, p. 158, ISBN 9780080963198. - ↑ Gabbay, Dov M.; Kanamori, Akihiro; Woods, John (2012),
*Sets and Extensions in the Twentieth Century*, Handbook of the History of Logic,**6**, Elsevier, p. 465, ISBN 9780080930664.

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