Nialpdromes: digits in base 16 are in nonincreasing order.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =8a(9) =9a(10) =10a(11) =11a(12) =12a(13) =13a(14) =14a(15) =15a(16) =16a(17) =17a(18) =32a(19) =33a(20) =34a(21) =48a(22) =49a(23) =50a(24) =51a(25) =64a(26) =65a(27) =66a(28) =67a(29) =68