Fixed points of iteration in A077091.

Terms

a(0) =0a(1) =4a(2) =24a(3) =8064a(4) =34944a(5) =35520a(6) =38880a(7) =69480a(8) =268560a(9) =420096a(10) =1054944a(11) =2946560a(12) =3054080a(13) =5660160a(14) =6621120a(15) =9768960a(16) =10264320a(17) =25885760a(18) =29062656a(19) =33933312a(20) =36484992a(21) =38707200a(22) =78532608a(23) =163418112a(24) =260601600a(25) =458987520a(26) =4044349440