reserve a,b,c,k,m,n for Nat;
reserve p for Prime;

theorem
  181 satisfies_Sierpinski_problem_76a
  proof
    let x be Nat;
    assume 181 < x < 181+10;
    then 181 < x < 190+1;
    then 181+1 <= x <= 190 by NAT_1:13;
    then x = 182 or ... or x = 190;
    hence thesis by XPRIMES0:182,183,184,185,186,187,188,189,190;
  end;
