We present a certified declarative first-order prover with equality based on John Harrison's Handbook of Practical Logic and Automated Reasoning, Cambridge University Press, 2009. ML code reflection is used such that the entire prover can be executed within Isabelle as a very simple interactive proof assistant. As examples we consider Pelletier's problems 1-46.
Reference: Programming and Verifying a Declarative First-Order Prover in Isabelle/HOL. Alexander Birch Jensen, John Bruntse Larsen, Anders Schlichtkrull & Jørgen Villadsen. AI Communications 31:281-299 2018. https://content.iospress.com/articles/ai-communications/aic764
See also: Students' Proof Assistant (SPA). https://github.com/logic-tools/spa
[2018-07-21] Proof of Pelletier's problem 34 (Andrews's Challenge) thanks to Asta Halkjær From.