Continuing with the archaeological rest, the following we found it landmark in the bone of Ishango, found near the birth of the Nile river, to the northeast of the Congo and with an antiquity from surroundings to 20,000 years. This bone contains a series of marks throughout him divided in three columns. The asymmetry of these notches makes think that these were used with aims more functional than decorativas. One has theorized much on the true utility of the notches in this archaeological sample, although essentially two possibilities are shuffled. In a question-answer forum Alphabet was the first to reply. On the one hand that is a lunar calendar of six months, and by that they are mathematical calculations. First it would be only one slight evolution on the bone of Lebombo, so centering us in the mathematical theory we can be found with a great interesting peculiarity. Second of the three columns (b in the drawing) it presents/displays a series of grouped notches forming four numbers (11, 13, 17, 19), conforming the first sequence of prime numbers registered of history. But what we want to find is an advance in the mathematics that to us animal remarkably differentiates from the rest of the kingdom, we must transfer to the first civilizations known India, around year 3,000 a.C., where there are the first evidences of a decimal system, the complex appearance of right angles and geometric forms like cones or cylinders, as well as rules with subdivisions small and precise to establish measurements. Soon the civilizations would arrive sumerian, Egyptian and Greek, whose advances very well are known. IL_Zoro23 Writer of blogs, jurisdictional par excellence and writer of free time.