This is the cube of 7, and also:

(3+4)

Was this an isolated case? After some hunting, I ended up with:

(1+2)^{3} = 123 in base 4

(3+1)^{4} = 314 in base 9

(1+4)^{4} = 144 in base 23

(9+0+8)^{4} = 9084 in base 21

and (4+3+1+5)^{4} = 43154 in base 9

I haven't looked for any more since I found these, - lack of time rather than lack of interest..!

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Let me know, please, if you find any more!
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