Use Trace to Evaluate a Sequence Equation
You are going to love using the Trace feature on the TI-84 Plus to evaluate sequences. Remember, you are not tracing x-values as you do in Function mode. Follow these steps to evaluate a sequence at specific n values:
See the first screen. Your trace starts at the smallest n value on the graph. The values of X and Y are displayed in the border at the bottom of your graph screen.
The TI-84 Plus C displays functions and information in the border of the graph screen. The TI-84 Plus displays similar information directly on the graph screen.
Press the right-arrow key to find the next term in the sequence.
Notice, your cursor jumps from one point to the next.
Enter a specific n value.
After pressing [TRACE], entering a number opens up an entry line in the border at the bottom of your graph screen.
While using Trace, you can enter a specific n value that is larger than the Xmax. As long as you enter a value smaller than nMax, you won't get an error message! See the second screen.
You don’t need a graph to evaluate a sequence. Instead, use your calculator by pressing [2nd][MODE]. Enter u by pressing [ALPHA][TRACE][ENTER], then press [(] and the n-value you would like to evaluate. See the third screen.