We are given x^3+3367=2^n
We know $3367=7 * 13 &*37
So let is work x^3=2^n \pmod 7
Working in mod 7 we have x^3 \in \{1,-1,0\} and 2^n \in \{1,2,4\} so we get 1 as common and for that n has to be multiple of 3.
So we get
x^3= 2^{3k} \pmod 7
Going back to the original equation we get
x^3 + 3367 = 2^{3k}
Or (2^k)^3 - x^3 = 3367
Or y^3 -x^3 = 3367 where y = 2^k
As (y-x) | y^3-x^3 so y-x | 3367\cdots(1)
Further
As we know (y-x)^3 = y^3-3y^2x + 3yx^2 - x^3 = (y^3-x^3) - 3yx(y-x) \lt y^3-x^3 when y-x \gt 0
So y-x\lt 15\cdots(2)
So y-x \in \{1,7\}\cdots(2) from (1) and (2)
y-x =1
gives x^3 + 3367 = (x+1)^3 = x^3 + 3x^2 + 3x + 1
Or 3367 = 3x^2+ 3x + 1
Or 3x^2+3x = 3366
Or x^2 + x = 1122
x = 33 and y = 34 and y is not power of 2 so not a solution
y-x=7
gives
x^3 + 3367 = x^3 + 21x^2 + 147 x + 343
or $3024 = 21x^2+ 147x
or x^2+ 7x = 144
or x = 9 or x=-16
only positive value admissible giving x = 9 and y = 16
2^n = y^3 giving 2^n = 2^{12} or n = 12
Hence x=3 , n = 12
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