What number comes next: 8, 72, 46, 521, 612, ? - Show how?

Answer 1

A sequence of cubes written backwards:


1, 8, 72, 46, 521, 612, 343, 215, 927, 1, ...

1^3= 1; 2^3 = 8, 4^3 = 64 and backwards is 46, 5^3 = 125 and backwards is 521, ... , 7^3= 343 and backwards is the same; etc....

(1^3 = 1 x 1 x 1) etc...

Answer 2

There doesn't seem to be a pattern when it comes to the numbers themselves, but when it comes to the digits, there is, though there isn't enough of a pattern to be sure.
The first number is 8. If you add the digits up for the second number, it comes out to 9. The digits 46, when added, add up to 10. The number 521, if you add the digits as single numbers, is 8 and 612, when the digits are added, comes to 9. So, the sequence, when you add up the digits of the individual numbers, is: 8, 9, 10, 8, 9... That means that the next number in the sequence should have digits that add up to 10, such as: 325 or 631 or 434. The problem with your number sequence is that the number 46 seems out of place when all the other numbers are in ascending order. I doubt there is a formula associated with these numbers.