Hi everyone,
What is the general formula of the number of the different ways to write a natural number based on the sum of lesser or equal naturals. For example:
5=1+1+1+1+1
=2+1+1+1
=2+2+1
=3+1+1
=3+2
=4+1
=5
In this case 5 can be written by 7 different ways.
Note: the order of the numbers of the sum is not important. Ex: 3+1+1 <=> 1+3+1 <=> 1+1+3
Thanks in advance