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…Rev NC
This approximation is accurate to within 0.2% of the tabulated values for sample sizes greater
than or equal to 16.
2.2.2.2 One-sided A-basis tolerance factors, kA, for the normal distribution
The exact computation of kB values is 1
n times the 0.95th quantile of the noncentral
t-distribution with noncentrality parameter 2.326 n and n…
https://www.wichita.edu/industry_and_defense/NIAR/Research/cytec-5320-1/T650-3k-PW-3.pdf