How many positive integers less than 1000, are there such that the equation has a solution for ?
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If x = 1, then α = 1
If 2 ≤ x < 3, the exponent will be 2, so:
x = 4 = 2 → α = 4
x = 5 → α = 5
x = 6 → α = 6
x = 7 → α = 7
x = 8 → α = 8
We stop at 8 because ⌊ 9 ⌋ = 3, which changes the exponent. So:
If 3 ≤ x < 4, the exponent will be 3, so:
x = 3 2 7 = 3 → α = 27
x = 3 2 8 → α = 28
⋮
Again, for x = 3 6 4 the exponent changes, so:
If 4 ≤ x < 5, the exponent will be 4, so:
x = 4 2 5 6 = 4 → α = 256
x = 4 2 5 7 → α = 257
⋮
Again, for x = 4 6 2 5 the exponent changes, so:
If 5 ≤ x < 6, the exponent will be 5. But 5 5 = 3125 > 1000.
So, α can only be {1, 4, 5, 6, 7, 8, 27, 28, 29, ... ,63, 256, 257, 258,.... 624}, which gives 412 possible values