Sum of distinct residues of all factorials mod 2^n.

Terms

a(0) =0a(1) =1a(2) =3a(3) =9a(4) =17a(5) =49a(6) =153a(7) =281a(8) =665a(9) =1433a(10) =3225a(11) =7705a(12) =17945a(13) =47641a(14) =64025a(15) =129561a(16) =293401a(17) =752153a(18) =1341977a(19) =2914841a(20) =6421017a(21) =14547481a(22) =33421849a(23) =71170585a(24) =138279449a(25) =247331353a(26) =645790233a(27) =1182661145a(28) =2558392857a(29) =5779618329