There is no pattern
after -9 it is -15 then -21, -27 and the ninth is -36
tn = 3n or 3*3* ... *3 (where there are n threes.)
arrange the no. ascending and use the formula (n+1)/2=nth number...arranged no. :20 23 25 25 27 27 27 29 31 35 37 41 43n is the number of the numbers...substitute: (13+1)/2= 7th no. from the arranged numbers...so the answer 27
The first four terms are 3 9 27 81 and 729 is the 6th term.
Willies
Assuming 20 is n = 1, then the formula would be:27-7n
The nth term of the sequence is (n + 1)2 + 2.
The nth term is: n^2 +2 and so the next number will be 38
n3
5n+2
2n +29
each time the number increases by 8 and the original number was 3.This means that nth term = 3+(n-1)8ie. the fourth term 27 would be 3 + (4-1)x8 = 3+24 = 27
The 38th term
3^n These are powers of 3
the anser is that you are stupid
9 3 1