1372744

Appears in sequences

• Consider all distinct functions f representable as x -> x^x^...^x with n x's and parentheses inserted in all possible ways; sequence gives difference between numbers of f with f(0)=1 and numbers of f with f(0)=0, with conventions that 0^0=1^0=1^1=1, 0^1=0.at n=19A211192
• G.f. A(x) satisfies: A(x) = 1 - x^2 * A(x/(1 - x)) / (1 - x).at n=16A336970