1. 13, 18, 23, 28, 33, 38, 43, 48, 53.
Conjecture: we add five to the next number 13+5: 18; 18+5: 23.
2. 512, 256, 128, 64, 32, 16, 8, 4, 2
Conjecture: Dividing the numbers by 2. 512/2: 256; 256/2:128.
3. 1, 8, 27, 64, 125, 216, 343, 512, 729.
Conjecture: series of cubic numbers: the base multiplied by 3.
4. 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31.
Conjecture: prime numbers: are numbers that can only by divided by themselves and by unit
5. i, ii, iii, iv, v, vi, vii, viii, ix, x.
Conjecture: Roman numbers is a numerical system expressed by roman numerals.
