481335403domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumber of distinct functions f representable as x -> x^x^...^x with n x's and parentheses inserted in all possible ways giving result f(0)=1, with conventions that 0^0=1^0=1^1=1, 0^1=0.at n=24A222380Prime numbersat n=25423215