SOLUTION: Write an equation for the sequence of numbers below, in terms of n. 3 6 10 15 21

Algebra ->  Sequences-and-series -> SOLUTION: Write an equation for the sequence of numbers below, in terms of n. 3 6 10 15 21      Log On


   

Question 979587: Write an equation for the sequence of numbers below, in terms of n.
3 6 10 15 21
Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!

a%5B1%5D = 3
a%5B2%5D = 6
a%5B3%5D = 10
a%5B4%5D = 15
a%5B5%5D = 21

General formula:  a%5Bk%5D = a%5Bk-1%5D + %28k%2B1%29,
for  k = 2, 3, 4, 5.