## Solution - Challenge 67 - Generate a Particular Sequence

Below is a possible solution to the problem **Challenge 67 - Generate a Particular Sequence** -

This consists of 2 logic.

- Generate Triangular number. The formula for which is n*(n+1)/2
- Generate Column Labels (A, B, AA, ZZ....) from numbers, the formula for which is

=SUBSTITUTE(ADDRESS(1,3,4),1,"") where 3 is for column C. So, we need to vary this 3.

The combined formula would be -

=SUBSTITUTE(ADDRESS(1,(ROW(1:1)-1)*ROW(1:1)/2+1,4),1,"")