# 
# Numerical Mathematics and Computing, Fifth Edition
# Ward Cheney & David Kincaid
# Brooks/Cole Publ. Co.
# (c) 2004
#
# file:  cp8_2_1
#
# Computer Problem 8.2.8
#
#GS original problem
#
x := 0;
y := 0;
for n from 1 to 20 do
 x := y/3 + 2/3; evalf(%);
 y := x/4 - 1/2;evalf(%);
end do;# 
#
# GS part b
#
x := 0;
y := 0;
for n from 1 to 20 do
 x := 3*y + 6; evalf(%);
 y := 2*x - 4;evalf(%);
end do;