如何保存shell的输出？

Question

I want to save this in a file form the shell:

Type the number of steps N
10
Type the initial values ti and ai
0
1
 23.000000 24.000000 
 46.000000 576.000000 
 69.000000 13824.000000 
 92.000000 331776.000000 
 115.000000 7962624.000000 
 138.000000 191102976.000000 
 161.000000 4586471424.000000 
 184.000000 110075314176.000000 
 207.000000 2641807540224.000000 
 230.000000 63403380965376.000000 
 253.000000 1521681143169024.000000 

how to do it? it does not work by just typing:

>./a.out>lalalla.txt

Answer 1

do

script filename.txt

Run the program, then type exit at the prompt

The session will be in filename.txt