reserve i,j,k,n,m,l,s,t for Nat;
reserve a,b for Real;
reserve F for real-valued FinSequence;
reserve z for Complex;
reserve x,y for Complex;
reserve r,s,t for natural Number;

theorem Th41:
  j<=l & j<>0 implies j divides l!
proof
  assume that
A1: j<=l and
A2: j<>0;
  ex k being Nat st l=j+k by A1,NAT_1:10;
  hence thesis by A2,Th40;
end;
