The notions of decidability and effective enumerability are applicable not only to sets of expressions but also to sets of integers or to a set of pairs of expressions or integers. Prove that a set A of expressions is effectively countable if and only if there exists a decidable set B of pairs〈a,n〉(consisting of an expression α and an integer n) such that A=dom B.

The notions of decidability and effective enumerability are applicable not only to sets of expressions but also to sets of integers or to a set of pairs of expressions or integers. Prove that a set A of expressions is effectively countable if and only if there exists a decidable set B of pairs〈a,n〉(consisting of an expression α and an integer n) such that A=dom B.

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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