a(n) = 400 * n + 1.

Terms

a(0) =401a(1) =801a(2) =1201a(3) =1601a(4) =2001a(5) =2401a(6) =2801a(7) =3201a(8) =3601a(9) =4001a(10) =4401a(11) =4801a(12) =5201a(13) =5601a(14) =6001a(15) =6401a(16) =6801a(17) =7201a(18) =7601a(19) =8001a(20) =8401a(21) =8801a(22) =9201a(23) =9601a(24) =10001a(25) =10401a(26) =10801a(27) =11201a(28) =11601a(29) =12001