Observe the following column numbers: 1, 6, 11, 16, 21 (1) Write the expression of its nth number (2) which number is equal to 2006?

Observe the following column numbers: 1, 6, 11, 16, 21 (1) Write the expression of its nth number (2) which number is equal to 2006?


(1) The expression of its nth number 5n-4
(2) 5N - 4 = 2006, n = 402, its 402nd number is equal to 2006