7829424domain: NAppears in sequencesn-th derivative of x^(x^(x^(x^x))) at x=1.at n=9A179505Ninth derivative of f_n at x=1, where f_n is the n-th of all functions that are representable as x^x^...^x with m>=1 x's and parentheses inserted in all possible ways.at n=16A215839