amsey1382 wrote:
Q. n is an integer greater than or equal to 0. The sequence Tn for n>0 is defined by Tn = Tn-1 + n. If T0 = 3, is nth Term, i.e. Tn even ?
1) n+1 is divisible by 3
2) n-1 is divisible by 4
I tried to solve this.
Testing 1st premise:If your prepare the list , it will come something like : 3,4,6,9,13,18,24,31,39,48,58,69,81,94,108,123,139,156..
if you notice the sequence become..OEEOOEEOOEEOOEEOO... IF n+1 is divisible by 3 ..n has to be 2,5,8,11,14..term...clearly ,this gives that Tn can be even or odd..so Insufficient.
Testing 2nd premise:if n-1 is divisible by 4 , term has to be 5,9,13,17,21..and so on...if you notice, this will always give an even number , because sequence OEEO repeats at every 4th term, giving O in every 4th
SO B is sufficient . didn't have OA , that's why posted ?