The following numerical integral within a numerical integral:
NIntegrate[ Exp[ -NIntegrate[ 1/(y - (1 - Exp[-(5/6) + (2 y)/3])), {y, z, 1}]] , {z, -(3/2) ProductLog[-(2/(3 E^(5/6)))], 1}] gives "NIntegrate::nlim: y = z is not a valid limit of integration" error messages prior to giving an estimate 0.250255.
How might I revise my code to avoid the errors? If the estimate is not valid, please explain why to me. Thank you!