look for an addition/subtraction or multiplication/division patterns between numbers in the sequence.
1, 4, 9, 16, ...
if you look at what you add to get to the next number.
+3, +5, +7, ...
the pattern is adding consecutive odd numbers
16+9 = 25
25+11 = 36
36+13 = 49
1, 4, 9, 16, 25, 36, 49, ...