Mathematics for IGCSE & O level - Sequences (Section 3 - No. 9)
What is the formula for the nth term of the sequence: 1, 3, 6, 10, ...?
n
n^2
n(n+1)/2
2n-1
ব্যাখ্যা
This is a triangular number sequence; each term is the sum of consecutive natural numbers.