one ,four ,eight ,(  ),nineteen; 1, 4,  8,(   ),19

问题描述:

one ,four ,eight ,(  ),nineteen; 1, 4,  8,(   ),19
括号里面应该是什么数字?原本题目是英文的.求该数字并写出理由

one ,four ,eight ,(thirteen),nineteen; 1, 4,  8,( 13  ),19
1+3=4+4=8+5=13+6=19