radius of curvatureradius of gyrationradius of torsionradius of torsion of a space curveradius vectorradixradix pointradon measureradon nikodym derivativeradon nikodym theoremrae of coolingrailroad carraiseraise a number to powerraising a number to a powerrake angleraker setram travelramanujan conjectureramanujan graphramificationramification indexramification pointramified elementramprandomrandom access memoryrandom aspectsrandom causes of variationrandom currentrandom digitrandom digits tablerandom distributionrandom errorrandom eventrandom experimentrandom functionrandom mannerrandom matrixrandom modelrandom noiserandom numberrandom number generationrandom numbersrandom orderrandom ordered samplerandom processrandom prospectrandom samplerandom sampling