Integral of sin(x) from 0 to 99*pi in 7530 recursions (correct value is 2):
2.000000007840077

Integral of exp(-x^2) from -4 to 4 in 82 recursions (correct value is ~ sqrt(pi) = 1.77245):
1.7724474685873817

Integral of ln(x)/sqrt(x) from 0 to 1 using 8602 integrand evaluations (correct value is -4):
-3.999917058999152

Integral of 4*sqrt(1-(1-x)^2) from 0 to 1 using 61182 integrand evaluations (correct value is pi = 3.141592653589793):
3.141592653589793