One unary function says less than two in existential second order logic

✍ Scribed by Bernd Loescher

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 643 KB
• Volume: 61
• Category: Article
• ISSN: 0020-0190
• DOI: 10.1016/s0020-0190(96)00198-6

✦ Synopsis

We show that the set of square numbers is the spectrum of an ~' ,,,-sentence (existential second order logic with quantification over unary function variables) with two unary function variables, but it is not the spectrum of IQ;,,-sentences with only one unary function variable. @ 1997 Elsevier Science B.V.