Un = 7 - 3*n
Chat with our AI personalities
1254
The 'n'th term is [ 4 - 3n ].
To find the nth term of this sequence, we first need to identify the pattern. The differences between consecutive terms are 5, 9, 13, 17, and so on. These are increasing by 4 each time. This means that the nth term can be calculated using the formula n^2 + 4n + 1. So, the nth term for the sequence 5, 10, 19, 32, 49 is n^2 + 4n + 1.
The nth term is: 5-2n
The formula for the nth triangular number is n(n+1)/2. Therefore, the fourth triangular number is equal to 4 x (4+1) / 2 = (4 x 5) / 2 = 10. The fiftieth triangular number is equal to 50 x (50+1) / 2 = (50 x 51) / 2 = 1275.