Two possible answers spring immediately to mind. First, this sequence appears to be a list of the first five prime numbers; in this case, the next number in the sequence would be 13. Second, the intervals between these numbers comprise the sequence "1 2 2 4", in which the nth number equals the product of the (n-1)th and (n-2)th numbers. Based on this, the next number in the given sequence would be 11 + (4*2) = 19.
23
These are all prime numbers. The next one is 17
42 is the next number in this sequence. This number sequence is adding the next prime number to the last number. So 1 + 2 = 3. Then 3 + 3 = 6, 6 + 5 = 11, 11 + 7 = 18, 18 + 11 = 29. The next prime number after 11 is 13, so 29 + 13 = 42. The next numbers would be 59 (42+17), 78 (59+19), and 101 (78+23)
This list of numbers is the list of prime numbers. Following 11, the next two numbers in the list are 13 and 17.
14
11
-3, -6, -11
11
The next number in the sequence would be 23. The sequence consists of prime numbers.
23
14
These are all prime numbers. The next one is 17
42 is the next number in this sequence. This number sequence is adding the next prime number to the last number. So 1 + 2 = 3. Then 3 + 3 = 6, 6 + 5 = 11, 11 + 7 = 18, 18 + 11 = 29. The next prime number after 11 is 13, so 29 + 13 = 42. The next numbers would be 59 (42+17), 78 (59+19), and 101 (78+23)
Sequence is +4 - 3 + 5 - 2 + 6 - 1 (+1 - 1)2 6 3 8 6 12 next number 11
17, it's the sequence of primes.
it has to be 11