Is this a general rule? Because with my primitive checking, all sum of first n cubes add to the square of a triangle number.

1^2 = 1^3 = 1

(1+2)^2 = 1^3 + 2^3 = 9

(1+2+3)^2 = 1^3 + 2^3 + 3^3 = 36

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