Numbers with exactly 2 1's in ternary expansion.

Terms

a(0) =4a(1) =10a(2) =12a(3) =14a(4) =16a(5) =22a(6) =28a(7) =30a(8) =32a(9) =34a(10) =36a(11) =38a(12) =42a(13) =44a(14) =46a(15) =48a(16) =50a(17) =52a(18) =58a(19) =64a(20) =66a(21) =68a(22) =70a(23) =76a(24) =82a(25) =84a(26) =86a(27) =88a(28) =90a(29) =92