The CAS Registry Mumber 134141-01-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,4,1,4 and 1 respectively; the second part has 2 digits, 0 and 1 respectively. Calculate Digit Verification of CAS Registry Number 134141-01: (8*1)+(7*3)+(6*4)+(5*1)+(4*4)+(3*1)+(2*0)+(1*1)=78 78 % 10 = 8 So 134141-01-8 is a valid CAS Registry Number.