Hofstadter–Conway $10,000 sequence is a famous sequence, which is defined as $a_1 = a_2 = 1,\, a_{n} = a_{a_{n-1}} + a_{n-a_{n-1}}\, (n \ge 3).$

Hofstadter–Conway \$10,000 sequence is a famous sequence, which is defined as 
$$ a_1 = a_2 = 1,\,   a_{n} = a_{a_{n-1}} + a_{n-a_{n-1}}\, (n \ge 3). $$

另外翻译也要补上一个美元符号（