13, because if you add the last number to the current number you get the next number
You are multiplying each number in the sequence by -2. Therefore, the next number in the sequence after 32 is -64.
These are Fibannoci's numbers. Therefore, the 7th number is 21.
1, 1 and 2
The nth term of the sequence is 3n - 2.
-64
4
You are multiplying each number in the sequence by -2. Therefore, the next number in the sequence after 32 is -64.
27
9
14
3,5,8,13 is followed by 21. 1,1,2,3,5,8,13,21,34,55,... is the Fibonacci series or Fibonacci sequence where the next number in the sequence is the sum of the last two numbers (1+1=2, 1+2=3, 2+3=5, etc.)
These are Fibannoci's numbers. Therefore, the 7th number is 21.
The number implied by the word 'tertiary' is 3. It comes after primary (1) and secondary (2) in a sequence.
15
The next number is -20. The sequence appears to be the Fibonacci sequence but it is not. One possibility is that it is the sequence generated by the polynomial: t(n) = (-17n6 + 369n5 - 3095n4 + 12795n3 - 27128n2 + 27876n - 10080)/720 for n = 1, 2, 3, ...
This sequence is the squaring of the numbers 1, 3, 5, and 7. The next number is 9^2 = 81.
21