Find the missing number in this series: 6, 12, 18, 49, 169, 361, 512, ?, 8000

Answer 1

The series advances in a set of three as shown below
(6)^1, (6+6)^1, (6+6+6)^1, (7)^2, (7+6)^2, (7+6+6)^2, (8)^3, (8+6)^3, (8+6+6)^3....... so on.
The question mark corresponds to (8+6)^3 = 14^3 = 2744.

Answer 2

Reason
Series = (x,2x,3x),((x+1)^2,(2x+1)^2,(3x+1)^2),((x+2)^3,(2x+2)^3,(3x+2)^3)
Clearly x=6
Therefore the missing number = 2744