U11ttU12isNatU12ttttU21ttttU41ttU42isNatisNatttisNatU11isNatisNatU21isNatplusN0U31isNatplusNsMU41isNatU31ttNU42ttsplusNM2.1isNatisNatU11isNatU11isNatU11AProVEunknownStatistics for single proof: 100,00 % (1 real / 0 unknown / 0 assumptions / 1 total proof steps)http://aprove.informatik.rwth-aachen.deJohnDoe