Any number that you choose can be the next number. It is easy to find a rule based on a polynomial of order 4 such that the first four numbers are as listed in the question followed by the chosen next number. There are also non-polynomial solutions. Short of reading the mind of the person who posed the question, there is no way of determining which of the infinitely many solutions is the "correct" one.
One possible rule, based on a polynomial of order 3 is
U(n) = (-4*n^3 + 33*n^2 - 53*n + 36)/3 for n = 1, 2, 3 and, accordingly, U(5) = 32.
But it is also possible to have
U(n) = (-4*n^4 + 36*n^3 - 107*n^2 + 147*n - 60)/3 which would give U(5) = 0
or
U(n) = (-31*n^4 + 278*n^3 - 821*n^2 + 1126*n - 456)/24 which would give U(5) = 1, and so on.
If you mean: 9, 19, 39, 69 then the next number in the sequence is 109
The rule of this pattern is -2 + 6 +4 so the next number would be 16.
12
75
16.
16384
the answer is 72.:)
304. Each number is twice the previous number.
34
2+3=53+5=85+8=1313+21=3333 is the next number in this pattern. This pattern is called a Fibonacci.
0.5 the pattern is the any given number is half of the number before it
33