Any number that you choose can be the next logical number. It is easy to find a rule based on a polynomial of order 3 (a cubic) such that the first three 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.For example,The next number is 5 if you use the rule U(n) = -10*n^3 + 69*n^2 - 134*n + 77
The next number is 11 if you use the rule U(n) = -9*n^3 + 69*n^2 - 123*n + 71
The next number is 17 if you use the rule U(n) = -8*n^3 + 69*n^2 - 112*n + 65
Intermediate values can be obtained with fractional coefficient.The next number is 5 if you use the rule U(n) = -9.833...*n^3 + 68*n^2 - 132.166...*n + 76 or
U(n) = (-59*n^3 + 408*n^2 - 793*n + 456)/6
677 is one possibility.
10
From the pattern (n + 4, n + 2, n + ?) I would say the next following number is 20 (n + 1).
A single number, such as 3773949588525642992, does not constitute a sequence.
3.3.5.4.4.6 It seems that the sequence takes the doubled numbers than adds two to the said number, such as five. So with that theory it would be logical that six would come after the doubled fours.
21. Add the last 2 numbers to get the next.
10
10
5
8
62
17?
6
The numbers are increasing by 1,4,9,16,25,36.... which are square numbers so the next increase is 49. Making the next number in the sequence 141
21. This is the Fibonacci series.
From the pattern (n + 4, n + 2, n + ?) I would say the next following number is 20 (n + 1).
A single number, such as 3773949588525642992, does not constitute a sequence.
34. Each number is the sum of the two preceding numbers. This is called the Fibonacci Sequence.