Number of divisor chains of length n which begin with n ("anchored" divisor chains).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =5a(8) =4a(9) =3a(10) =2a(11) =8a(12) =4a(13) =6a(14) =47a(15) =44a(16) =6a(17) =37a(18) =6a(19) =166a(20) =462a(21) =232a(22) =372a(23) =2130a(24) =1589a(25) =9093a(26) =20896a(27) =20314a(28) =4118a(29) =32367