13. Joe and Blair take turns counting from 1, each person counting one more number than the last number counted in the previous round. If Joe starts with 1, Blair then counts 1, 2, Joe then counts 1, 2, 3, and so on, then the 53rd number counted is ( ).
(A) 2
(B) 3
(C) 5
(D) 6
(E) 8