3 5 33 x 503 1233
here
5 - 3 = 2 ( 1 cube + 1 = 1 + 1 = 2 )
33 - 5 = 28 ( 3 cube + 1 = 27 + 1 = 28 )
we should skip 3rd and 4th step because we are not know the value of x
now last step
1233 - 503 = 728 ( 9 cube + 1 = 729 + 1 = 728 )
we absorb that the difference between the no. is a series is the sum of cube of odd no. and 1
so third step
x - 33 = 5 cube +1 = 125 + 1 = 126
x = 126 + 33 = 159
3 5 33 159 503 1233
159
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