ak kai zap tah = more 5.
16.

ak kai shak pah = more 6, etc.
A still more primitive structure is shown in the numerals of the Mboushas[99] of Equatorial Africa.

Instead of using 5-1, 5-2, 5-3, 5-4, or 2d 1, 2d 2, 2d 3, 2d 4, in forming their numerals from 6 to 9, they proceed in the following remarkable and, at first thought, inexplicable manner to form their compound numerals: 1.

ivoco.
2.

beba.
3.