Number of integers less than A000108(n) relatively prime to A000108(n).

Terms

a(0) =1a(1) =1a(2) =1a(3) =4a(4) =6a(5) =12a(6) =40a(7) =240a(8) =480a(9) =1920a(10) =6912a(11) =20736a(12) =76032a(13) =253440a(14) =608256a(15) =4257792a(16) =7983360a(17) =26611200a(18) =88704000a(19) =319334400a(20) =1277337600a(21) =5109350400a(22) =19508428800a(23) =73156608000a(24) =336520396800