Respostas

2014-03-19T11:49:55-03:00
Os números naturais entre 2 e 21 são : { 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 } 
1 5 1
2014-03-19T11:50:11-03:00
3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20