Nguyen-5: sin(x^2) cos(x) - 1 from 20 points in [-1, 1]
8 islands of 500 trees, until the RMSE is at most 1.66e-11

Target after 2 generations and 10670 evaluations
RMSE on the 20 training points: 0.00e0
RMSE on the 100 test points:    0.00e0

the expression, 11 nodes of depth 4, and its scaling:
-1 + 1 * (mul(cos(x), sin(mul(mul(x, x), pdiv(x, x)))))
