378764280domain: NAppears in sequencesn-th derivative of ((x^x)^x)^(x^x) at x=1.at n=10A215707Tenth 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=9A215840