Digit power sum
The number 512 is interesting because it is equal to the sum of its digits raised to some power: 5 + 1 + 2 = 8, and 83 = 512. Another example of a number with this property is 614656 = 284.
We shall define an to be the nth term of this sequence and insist that a number must contain at least two digits to have a sum.
You are given that a2 = 512 and a10 = 614656.
512是一个有趣的数，因为它等于其各位数字和的幂：5 + 1 + 2 = 8，而83 = 512。拥有同样性质的数的另一个例子是614656 = 284。
已知a2 = 512以及a10 = 614656。