What is the b'th term of 17, 28, 47, 74, 109?
-
What is the k'th term of -2, 3, 8, 13?
-
What is the t'th term of 3, -2, -11, -24, -41?
-
What is the f'th term of 167, 159, 147, 131, 111?
-
What is the b'th term of 450, 899, 1348, 1797?
-
What is the u'th term of -164, -169, -176, -185, -196, -209, -224?
-
What is the x'th term of -1535, -1543, -1549, -1553?
一个美术生