It seems that this numbers are connected to Dunbar's number[1] and that is related to i.e. military units organization[2]. In case of military units look at th

It seems that this numbers are connected to Dunbar's number[1] and that is related to i.e. military units organization[2]. In case of military units look at the end of page. Basic unit is squad (4-10 soldiers), next is platoon (3-4 squads/16-40 soldiers). [1] https://en.wikipedia.org/wiki/Dunbar's_number https://en.wikipedia.org/wiki/Dunbar's_number [2] http://www.army.mil/info/organization/unitsandcommands/oud/ http://www.army.mil/info/organization/unitsandcommands/oud/