Nialpdromes: digits in base 3 are in nonincreasing order.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =6a(6) =7a(7) =8a(8) =9a(9) =12a(10) =13a(11) =18a(12) =21a(13) =22a(14) =24a(15) =25a(16) =26a(17) =27a(18) =36a(19) =39a(20) =40a(21) =54a(22) =63a(23) =66a(24) =67a(25) =72a(26) =75a(27) =76a(28) =78a(29) =79