Numbers whose base-4 representation contains exactly three 1's and four 3's.

Terms

a(0) =5631a(1) =6015a(2) =6111a(3) =6135a(4) =6141a(5) =7551a(6) =7647a(7) =7671a(8) =7677a(9) =8031a(10) =8055a(11) =8061a(12) =8151a(13) =8157a(14) =8181a(15) =13695a(16) =13791a(17) =13815a(18) =13821a(19) =14175a(20) =14199a(21) =14205a(22) =14295a(23) =14301a(24) =14325a(25) =15711a(26) =15735a(27) =15741a(28) =15831a(29) =15837