Number of redundant function representations of x^x^...^x with n x's and parentheses inserted in all possible ways.

A216041

Number of redundant function representations of x^x^...^x with n x's and parentheses inserted in all possible ways.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =5a(5) =22a(6) =84a(7) =314a(8) =1144a(9) =4143a(10) =14954a(11) =54020a(12) =195526a(13) =709927a(14) =2586629a(15) =9459464a(16) =34722823a(17) =127923631a(18) =472950024a(19) =1754436962a(20) =6528898588a(21) =24369211839a(22) =91214280785a(23) =342315888666

External references