reserve X for set;
reserve a,b,c,k,m,n for Nat;
reserve i for Integer;
reserve r for Real;
reserve p for Prime;

theorem Th58:
  13 divides 3|^1105-3
  proof
    26 = 13*2;
    then 3|^3,1 are_congruent_mod 13 by Lm1109;
    then 3|^3|^368,1|^368 are_congruent_mod 13 by GR_CY_3:34;
    then 3|^1104*3|^1,1*3 are_congruent_mod 13 by Lm1134,INT_4:11;
    hence thesis by Lm1139;
  end;
