Catalan number analogs for totienomial coefficients (A238453).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =12a(5) =36a(6) =120a(7) =360a(8) =960a(9) =3840a(10) =13824a(11) =41472a(12) =152064a(13) =506880a(14) =2280960a(15) =7983360a(16) =29937600a(17) =99792000a(18) =266112000a(19) =1197504000a(20) =4790016000a(21) =19160064000a(22) =73156608000a(23) =219469824000