function F = KB81F(x)
%

F(1) = -0.99378+(1-x(2))+(1-x(1))+x(3)+x(4)+x(5)-(1-x(2))*(1-x(1))-(1-x(2))*x(3)-(1-x(2))*x(4)-(1-x(2))*x(5)-(1-x(1))*x(3)-(1-x(1))*x(4)-(1-x(1))*x(5)-x(3)*x(4)-x(3)*x(5)-x(4)*x(5)+(1-x(2))*(1-x(1))*x(3)+(1-x(2))*(1-x(1))*x(4)+(1-x(2))*(1-x(1))*x(5)+(1-x(2))*x(3)*x(4)+(1-x(2))*x(3)*x(5)+(1-x(2))*x(4)*x(5)+(1-x(1))*x(3)*x(4)+(1-x(1))*x(3)*x(5)+(1-x(1))*x(4)*x(5)+x(3)*x(4)*x(5)-(1-x(2))*(1-x(1))*x(3)*x(4)-(1-x(2))*(1-x(1))*x(3)*x(5)-(1-x(2))*(1-x(1))*x(4)*x(5)-(1-x(2))*x(3)*x(4)*x(5)-(1-x(1))*x(3)*x(4)*x(5)+(1-x(2))*(1-x(1))*x(3)*x(4)*x(5);
