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 Th45:
  5 divides 2|^1105-2
  proof
    2|^4|^276,1|^276 are_congruent_mod 5 by Lm1141,GR_CY_3:34;
    then 2|^1104*2|^1,1*2 are_congruent_mod 5 by Lm1129,INT_4:11;
    hence thesis by Lm1128;
  end;
