Number of proper divisors of n!.

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =7a(5) =15a(6) =29a(7) =59a(8) =95a(9) =159a(10) =269a(11) =539a(12) =791a(13) =1583a(14) =2591a(15) =4031a(16) =5375a(17) =10751a(18) =14687a(19) =29375a(20) =41039a(21) =60799a(22) =95999a(23) =191999a(24) =242879a(25) =340031a(26) =532223a(27) =677375a(28) =917279a(29) =1834559