21. Your example is in the Fibonacci series.
fibonacci sequence :)
It is called a Fibonacci number sequence! 1,1,2,3,5,8,13,21...
Fibonacci Sequence.
The answer is 21.Your numerical series is the beginning of a mathematical sequence called Fibonacci Numbers.The first number of the sequence is 0, the second number is 1, and each subsequent number is equal to the sum of the previous two numbers of the sequence itself (i.e. 0, 1, 1, 2, 3, 5, 8, 13, 21, etc.).
Fibonacci Sequence
It is the next odd number.
3
The next number in the sequence is 20. You are alternately multiplying the previous number by two and then subtracting two.
number two next to Christmas
51. Just add two to an odd number to work out the next ;)
512
no 81 is a square number the next square number is 100