What is the change in each term of the sequence? 1,4,13,40,121,

The next pattern is 364...

the pattern is by multiples of 3 added to the preceding number;

example, 1+3= 4 that's 3
4+9=13 because 3*3 is 9
13+27=40 coz 9*3 is 27
40+81=121 coz 27*3 is 81
121+243=364 coz 81*3 is 243

and so on and so forth..
hope this helps!