Nialpdromes: digits in base 5 are in nonincreasing order.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =10a(8) =11a(9) =12a(10) =15a(11) =16a(12) =17a(13) =18a(14) =20a(15) =21a(16) =22a(17) =23a(18) =24a(19) =25a(20) =30a(21) =31a(22) =50a(23) =55a(24) =56a(25) =60a(26) =61a(27) =62a(28) =75a(29) =80