The first term in a sequence is 1 and the second term…

The first term in a sequence is 1 and the second term is 21. From the third term on each term is the average (arithmetic mean) of all preceding terms. What is the 38th term in the sequence?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #88291