Plaindromes: numbers whose digits in base 3 are in nondecreasing order.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =5a(5) =8a(6) =13a(7) =14a(8) =17a(9) =26a(10) =40a(11) =41a(12) =44a(13) =53a(14) =80a(15) =121a(16) =122a(17) =125a(18) =134a(19) =161a(20) =242a(21) =364a(22) =365a(23) =368a(24) =377a(25) =404a(26) =485a(27) =728a(28) =1093a(29) =1094