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

theorem
  115 satisfies_Sierpinski_problem_76a
  proof
    let x be Nat;
    assume 115 < x < 115+10;
    then 115 < x < 124+1;
    then 115+1 <= x <= 124 by NAT_1:13;
    then x = 116 or ... or x = 124;
    hence thesis by XPRIMES0:116,117,118,119,120,121,122,123,124;
  end;
