isabelle/valid/imo_1987_p6.thy (15 lines of code) (raw):

(* Authors: Albert Qiaochu Jiang *) theory imo_1987_p6 imports Complex_Main "HOL-Computational_Algebra.Computational_Algebra" begin theorem imo_1987_p6: fixes p :: nat and f :: "nat \<Rightarrow> nat" assumes h0 : "\<And>x. f x = x^2 + x + p" and h1 : "\<And>(k::nat). (k\<le>floor(sqrt (q/3))) \<Longrightarrow> prime (f k)" shows "\<And>i. (i \<le> p - 2) \<Longrightarrow> prime (f i)" sorry end