Number of functions of n points with no fixed points and with no symmetries.

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =6a(5) =12a(6) =32a(7) =73a(8) =180a(9) =426a(10) =1041a(11) =2507a(12) =6113a(13) =14853a(14) =36283a(15) =88622a(16) =217054a(17) =532018a(18) =1306281a(19) =3210392a(20) =7899770a(21) =19456524a(22) =47966169a(23) =118346672a(24) =292228449a(25) =722098114a(26) =1785513052a(27) =4417719597a(28) =10936705897