Question

What is the next number in the sequence?

Answer 1

Looks like the next term in the sequence is generated by multiplying the previous term by 3 and adding 1:

$1\times3+1=4$
$4\times3+1=13$
$13\times3+1=40$
$40\times3+1=121$

If the pattern holds, the next term is probably going to be

$121\times3+1=364$