isabelle/valid/mathd_numbertheory_301.thy (13 lines of code) (raw):

(* Authors: Wenda Li *) theory mathd_numbertheory_301 imports Complex_Main "HOL-Computational_Algebra.Computational_Algebra" "HOL-Number_Theory.Number_Theory" begin theorem mathd_numbertheory_301: fixes j :: nat assumes "j>0" shows "(3 * (7 * j + 3)) mod 7 = 2" sorry end