把1英寸分成8等分: 1/8 1/4 3/8 1/2 5/8 3/4 7/8 英寸。 This is an arithmetic sequence since there is a common difference between each term. In this case, adding 18 to the previous term in the sequence gives the next term. In other words, an=a1+d (n−1). Arithmetic Sequence: d=1/8
