b=[19.97498333 39.94996666 19.97498333];
a=[68.2660915579 -0.0787823638 11.7126256859];
x=ones(1,10)
y=filter(b,a,x)
hold on; grid on;
plot(0:length(y)-1,y);
stem(0:length(y)-1,y);
axis([0,9,0.2,1.2]);
hold off